Entries in Terror Threat (20)


No 'Credible or Specific' Terror Threat on 9/11 Anniversary

Chip Somodevilla/Getty Images(NEW YORK) -- Intelligence sources tell ABC News that there is no "credible or specific" information that al Qaeda or any other terrorist organizations are plotting attacks timed to coincide with the 11th anniversary of 9/11.

Heightened vigilance in the nation's big cities and a strong, visible police presence at Ground Zero in New York will signify law enforcement's readiness to respond to any anniversary terror attack.

Federal and local counterterrorism officials tell ABC News that a heightened awareness of terror threats is now the "new normal."

"There is no credible or specific intelligence to indicate terrorist organizations are plotting attacks to coincide with the 11th anniversary of 9/11," Department of Homeland Security spokesman Matt Chandler told ABC News.  "However, we know from the intelligence gathered from the Osama bin Laden raid that al Qaeda has shown an interest in specific dates and anniversaries, such as 9/11."

Just before last year's anniversary, intelligence sources were hearing incessant "chatter" on radical Islamist websites and communications channels that some kind of attack was coming to mark the 10th anniversary.  Fortunately, nothing materialized, but officials said they were not letting down their guard.

"We continue to encourage our federal, state and local partners, as well as the American public, to remain vigilant and report any suspicious activity to local authorities," Chandler said.  "Our security posture, which always includes measures that are seen and unseen, will continue protect the American people."

Meanwhile, federal authorities have been communicating with their local and state counterparts through joint terrorism task forces reminding them to track any lead and check any tips.

A bulletin obtained by ABC News has already gone out, urging vigilance on the anniversary, noting that there has been little discussion heard or found online by authorities of how al Qaeda would mark the anniversary.

Nor was there any "overt" discussion of al Qaeda's failure to mark the 10th anniversary in the 12 months since.

A New York City official said that the New York Police Department would have a strong, visible presence at Ground Zero, where it now routinely deploys several hundred officers at a World Trade Center command center.

While 9/11 will never become just another day in America, keeping a close eye on any possible terror threat has become business as usual for law enforcement.

Copyright 2012 ABC News Radio


GAO: Hospitals' Failure to Secure Radioactive Materials Ups Terrorism Risk

iStockphoto/Thinkstock(WASHINGTON) -- Eleven years after the terrorist attacks of Sept. 11, 2001, the Government Accountability Office has released a report saying that hospitals have been negligent in securing the radioactive materials they use to treat cancer patients, potentially putting the materials in the hands of terrorists who could use them to make a dirty bomb.

While authorities have identified no specific plot or target for this 11th anniversary of 9/11, the GAO, the investigative arm of the U.S. Congress, has warned Congress about lapses in hospitals, many of which routinely use equipment containing these radioactive materials.

"Although we realize how important these facilities and equipment are, they have to be secured," Gene Aloise, director of national resources and environment at the GAO, said.

Nearly four out of five hospitals across the country have failed to put in place safeguards to secure radiological material that could be used in a dirty bomb, according to the report, which identifies more than 1,500 hospitals as having high-risk radiological sources. Only 321 of these medical facilities have set up security upgrades, according to the GAO review, which found some gaping lapses of security in 26 hospitals.

At one facility, for example, a device containing potentially lethal radioactive cesium was stored behind a door with a combination lock -- but the combination was written on the door frame.

At another, a machine containing almost 2,000 curies of cesium-13 was stored just down the hall from a loading dock near an unsecured window.

At a third, at least 500 people had unescorted access to radiological materials.

"In the hands of terrorists, these [radioactive materials] could be used to produce a simple and crude but potentially dangerous weapon," the GAO says.

According to the report, the National Nuclear Security Administration spent $105 million to complete security upgrades at 321 of more than 1,500 hospitals and medical facilities that were identified as having high-risk radiological sources. The upgrades include security cameras, iris scanners, motion detectors and tamper alarms.

But these upgrades are not expected to be completed until 2025, so until then, many hospitals and medical centers remain vulnerable, the GAO says.

The Nuclear Regulatory Commission challenged the GAO's findings, saying that the agency and its partners are vigilant about protecting hospitals and medical facilities, and had developed layers of security to do so.

The American Hospital Association has responded to the report, saying it is carefully reviewing the GAO's recommendations.

"Since September 11, hospitals across the country have been upgrading their disaster plans to meet today's new threats. Hospitals follow the Nuclear Regulatory Commission's regulations on how to secure radiological materials.  In addition, the Joint Commission, which accredits most hospitals, requires hospitals to ensure the safety and security of radioactive materials," the AHA said in a statement.  "Hospitals will carefully study the GAO recommendations.  America's hospitals are committed to working with NRC to strengthen security and protect their community."

Copyright 2012 ABC News Radio


Top Counter-Terrorism Official: No Further Threat from Bomb

ABC News(NEW YORK) -- The inside source who helped foil a U.S. bomb threat meant to coincide with the first anniversary of Osama bin Laden's death has been taken out of Yemen and is safely in Saudi Arabia, ABC News reported Tuesday morning.

When asked on ABC's Good Morning America if the source was the would-be bomber, President Obama’s top counter-terrorism advisor, John Brennan, wouldn't give a direct answer, but said, “We’ve been working very closely with our international partners to make sure that this device did not pose a threat to the American public.  We continue to work with them, there are some very sensitive operational aspects of this that we’re continuing to pursue.  So the means we were able to get this device we are trying to make sure that we protect, again, the equities that are involved with it.”

The FBI are examining the device, Brennan said, and although he can’t confirm that there aren’t other bombers at large he said that “neither the device nor the intended user of this device pose a threat” to the United States.

“Again we are working with our partners overseas to ensure that all measures are taken related to the device as well as to any individuals that might have been designed to use it,” he said.

The device is reported to be more sophisticated than that of the 2009 so called “Underwear Bomber,” with a better detonator and no metal.  But Brennan would not definitively say if the device could have gotten past airport security, had it gotten to that point.

“There are a number of measures in place at airports overseas.  We work with our partners.  They continually change those measures to stay abreast of the latest developments that we have been able to uncover in terms of the types of techniques and tactics used by terrorists groups,” Brennan said.

People flying should not be concerned, he said.  Instead, in light of the foiled attack, Americans should be confident that our intelligence is working.

“We don’t want to be complacent, feeling as though our security measures are as strong as they could be.  We continue to adapt and evolve them.  Again this IED was a threat from the stand point of the design…so now we are trying to make sure we are taking the measures that we need to prevent any other type of IED similarly constructed from getting thru security procedures,” Brennan said.

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Copyright 2012 ABC News Radio


Underwear Bomber Trial to Begin in Detroit

U.S. Marshals Service via Getty Images(DETROIT) -- The trial for underwear bomber Umar Farouk Abdulmutallab gets underway Tuesday in Detroit, where the 24-year-old Nigerian national faces charges for attempting to bomb Northwest Airlines Flight 253 on Christmas Day 2009 with 290 people on board.

The attempted attack left an indelible mark, exposing aviation security gaps and missed signals by U.S. intelligence and counterterrorism agencies in the post 9/11 era.  The attempted bombing has resulted in more robust and sometimes controversial passenger screenings and a ramping up of terrorist watch list efforts.

Abdulmutallab faces charges of attempted murder, attempted use of a weapon of mass destruction, willfully attempting to destroy an aircraft, placing a destructive device in proximity to an aircraft, and conspiracy to commit an act of terrorism.

It is expected at trial that the jury of nine women and three men will hear how Abdulmutallab transformed from a young man living in Nigeria to a hard-core radical who traveled to Yemen and sought out members of al Qaeda to undertake terrorist attacks against the United States.

The trial is also expected to yield new information about Abdulmutallab and his connections with the recently killed cleric Anwar al-Awlaki, who was killed Sept. 30 in a U.S. drone strike in Yemen.  Al-Awlaki has been at the center of numerous U.S. terrorism cases over the past two years with terrorism suspects either visiting his website or communicating with the cleric via e-mail.

According to statements Abdulmutallab allegedly provided to FBI agents after the attempted bombing, Abdulmutallab stated that he was inspired to undertake attacks after visiting al-Awlaki’s websites.

The trial will recount the terrifying moments aboard the plane as Abdulmutallab tried to detonate the device which was allegedly crafted by al Qaeda in the Arabian Peninsula’s master bomb maker Ibrahim Hassan Asiri.

Judge Nancy Edmunds has allowed the prosecutors to show the jury a video showing the destructive force a replica of Abdulmutallab’s underwear bomb could have had on the aircraft’s aluminum skin.  The government intends to call an explosives expert who will address why the device failed to detonate despite allegedly having almost 200 grams of the high-explosives Triacetone Triperoxide (TATP) and Pentaerythritol Tetranitrate (PETN).

The jury will hear from passengers that were aboard the aircraft who heard loud popping noises then smoke and fire coming from Abdulmutallab’s lap as the intended bomb smoldered and burned Abdulmutallab.  The flight attendants and passengers extinguished the flames and restrained Abdulmutallab who was detained and taken to a hospital for his burns.

Abdulmutallab, who has acted as his own attorney after he fired his initial team of defense counsel, will be able to question government expert witnesses and possibly the FBI agents who first took statements from him that he was a member of al Qaeda.

It is unclear how the accused al Qaeda member will act during the trial.  At times he has refused to rise before Judge Edmunds, he asked the judge if he could wear a traditional Yemeni dagger, a jambiya, in the courtroom during proceedings (the request was denied), and he has shouted outbursts that al-Awlaki is still alive.

Because of his unpredictable nature Abdulmutallab will also be represented by Anthony Chambers, a Detroit defense attorney who has acted as stand-by counsel to ensure Abdulmutallab receives a fair trial.

The trial is expected to last 3 to 4 weeks.

Copyright 2011 ABC News Radio


Jury Selection Begins in Trial of 'Christmas Underwear Bomber'

Comstock/Thinkstock(DETROIT) -- Jury selection will begin Tuesday in the terror trial of Umar Farouk Abdulmutallab -- the Nigerian man suspected of trying to detonate a bomb hidden in his underwear while aboard a Detroit-bound flight on Christmas Day 2009.

Had he been successful, Abdulmutallab could have killed the nearly 300 passengers aboard Northwest Airlines Flight 253.

The Detroit Free Press reports that out of an initial pool of 240 potential jurors, 132 remain, 40 of which will be questioned by both the prosecution and defense in Detroit on Tuesday.

The newspaper says Abdulmutallab, who's been dubbed the "Christmas Underwear Bomber," is representing himself, however, it is not yet known if he will handle the interrogation of the jurors without the help of his standby attorney.

Opening statements in Abdulmutallab's trial are slated to begin on Oct. 11.

Copyright 2011 ABC News Radio


American Indicted in Remote-Controlled Plane Terror Plot

FBI(WASHINGTON) -- A federal grand jury has indicted a 26-year-old American on terror charges relating to an alleged plot to strike the nation's capital with several explosive-laden, remote-controlled airplanes.

Rezwan Ferdaus, a U.S. citizen from Ashland, Mass., and Northeastern University physics graduate, was nabbed in an elaborate FBI sting after he told undercover officers exactly how he planned to arm "small drone airplanes" with explosives in order to hit the Pentagon and U.S. Capitol building before opening fire on the survivors, federal officials said in a statement.

Ferdaus was indicted on six counts, including "attempting to damage and destroy a federal building by means of an explosive" and "attempting to provide material support to terrorists."

An attorney for Ferdaus has not returned requests for comments on the charges against him.

According to the indictment, Ferdaus believed his attack could "decapitate" the U.S. "military center".

"Individuals, self-radicalized, they're not looking to cause big mass casualties like 9/11," said former FBI agent and ABC News consultant Brad Garrett, "because they're trying to inflict fear."

Federal officials said Ferdaus appeared to have been radicalized online by Islamist videos and writings.  By 2010, Ferdaus believed he was working for al Qaeda when he began modifying cellphones to serve as electrical switches for improvised explosive devices (IEDs) to be passed on to fighters in the Middle East.

"During a June 2011 meeting, he appeared gratified when he was told that his first phone detonation device had killed three U.S. soldiers and injured four or five others in Iraq.  Ferdaus responded, 'That was exactly what I wanted,'" the Department of Justice said in a statement after Ferdaus' arrest Wednesday.

The cellphones, however, never got anywhere near the Middle East as Ferdaus was actually handing them over to undercover officers for the FBI.  Still, Ferdaus appeared to want to do more, investigators said.

"Ferdaus envisioned causing a large 'psychological' impact by killing Americans, including women and children, who he referred to as 'enemies of Allah,'" the DOJ's statement said.  "According to the affidavit, Ferdaus' desire to attack the United States is so strong that he confided, 'I just can't stop; there is no other choice for me.'"

Ferdaus allegedly wanted to command a team of six operatives that would use up to three remote-controlled aircraft filled with explosives in the "aerial" part of the attack before firing on any survivors in a follow-up "ground" attack.

Federal investigators said Ferdaus traveled to Washington, D.C., to "conduct surveillance" and take photographs of his targets before acquiring his weapons, including six AK-47 assault rifles, grenades and what he believed to be C-4 explosives.

"Although Ferdaus was presented with multiple opportunities to back out of his plan, including being told that his attack would likely kill women and children, the affidavit alleges that Ferdaus never wavered in his desire to carry out the attacks," the DOJ said.

Copyright 2011 ABC News Radio


9/11 Threat Still Under Investigation But Aspects ‘Eliminated’

Chip Somodevilla/Getty Images(WASHINGTON) -- Officials from multiple agencies tell ABC News that after six days of the U.S. government pushing its law enforcement and intelligence agencies to full tilt, no significant evidence has turned up to confirm the recent terror threat allegedly aimed at Washington, D.C. and New York.

While some officials remain concerned about the rest of this week in particular, a number of sources say they are almost ready to exhale a little.

“We are getting close to a sigh of relief,” one official said.

Despite the threat information not being confirmed at this time, FBI Director Robert Mueller and Homeland Security Secretary Janet Napolitano said on Tuesday that the threat was still ongoing.

“The threat has not been resolved and until it is resolved it is an outstanding threat that we are following up on.  Even though Sept. 11 has now passed, we do not believe that that necessarily means we should back down,”  Mueller told the Senate Homeland Security and Government Affairs Committee.

“[The FBI], Department of Homeland Security, NCTC [The National Counterterrorism Center], the intelligence agencies are pursuing that as heavily as we have over the last several days and will continue to do so until it’s resolved,” Mueller said.

“We consider it an ongoing threat and we continue to lean forward into confirming that threat,” Napolitano said.

Last week, the DHS and FBI issued a joint bulletin based on threat information from a credible source that there was an ongoing plot to detonate vehicle-born bombs in New York City or Washington, D.C.  The threat prompted a massive police show of force in the cities and sent the intelligence community into a race to try and run the threat information to ground.

Mueller told the Senate Committee Tuesday some actions the FBI has taken: “Since we first had word of that threat we have conducted hundreds of interviews.  We have been pursuing a number of leads and consequently there.  As a result of that, we’ve been now able to eliminate some aspects where we thought that we ought to be looking in order to determine whether it was indeed a valid threat.  But there’s still work to be done.”

Matthew Olsen, the recently confirmed director of the National Counterterrorism Center told the Senate panel, “We’re not prepared to say that it’s been resolved and will continue to work to analyze it and share information about it.”

Copyright 2011 ABC News Radio


9/11 Anniversary Terror Plot? Feds Question, Clear 300 People

Somodevilla/Getty Images(WASHINGTON) -- The FBI has questioned and cleared some 300 people since Friday and still no hard evidence has emerged to corroborate early alarms of a potential Sept. 11 anniversary terror attack, U.S. officials told ABC News, leaving potentially deadly questions unanswered and security still on high alert.

Last week, intelligence emerged from what several officials called a single "credible" source that there was an ongoing plot to launch a vehicle-born bomb attack on New York City or Washington, D.C., prompting a federal bulletin to law enforcement, public announcements by top U.S. officials and a nationwide manhunt for three men.  Since the alarm was first raised, the CIA, FBI and a number of federal and local agencies have been unable to find any evidence to back up the original information.

And though none of the men have been found, the 10th anniversary of the Sept. 11, 2001 terror attacks passed relatively without incident on Sunday.  Federal and local law enforcement officials said that at least for a while, they won't be backing off the heavy, high-profile security that surrounded the anniversary.

According to former White House counter-terrorism advisor and ABC News consultant Richard Clarke, the business of pulling back on the massive security effort without a resolution to the bomb plot could be tricky business.

"They have to unwind the heavy security very slowly and in gradual steps -- make it appear that some of the heavy security has gone away while actually keeping a lot of surveillance the public won't see," Clarke said.

In New York, police officials said they would maintain the tough security at least through Monday morning.

"The threat for me is fundamentally the same.  It hasn't changed.  We don't have really additional information to add," NYPD Commissioner Raymond Kelly told ABC News' New York affiliate WABC-TV on Sunday, referring to the alleged bomb plot.  "But there's no reason to lessen our alert status."

The FBI will continue its expanded security effort through the day and perhaps as long as it takes to investigate the alleged bomb plot, law enforcement officials told ABC News.  The Department of Homeland Security is following suit, maintaining additional security at major transportation hubs and federal buildings.

In addition to the FBI interviews, a public alert about the potential plot also drew hundreds of citizen reports about suspicious packages and individuals.

In two separate instances on the 9/11 anniversary, fighter jets were scrambled to escort passenger planes after passengers on the flights allegedly acted "suspiciously."  But in both cases, the suspicious activity turned out to be non-terror-related -- one case of frequent bathroom trips, another of a couple "making out" in the lavatory, federal officials said Sunday.

Copyright 2011 ABC News Radio


Fevered Hunt for Potential Plotters Continues on 9/11 Anniversary

Chip Somodevilla/Getty Images(WASHINGTON) -- On the 10th anniversary of the Sept. 11, 2011, terror attacks, the U.S. intelligence and law enforcement apparatus continued a feverish, around-the-clock effort to find evidence to corroborate an unfolding terror plot.

By late Saturday, none was in hand.  However, the picture authorities were working from had been fleshed out substantially since the intelligence from Afghanistan arrived Wednesday.

Authorities now believe, like several self-radicalized American jihadists before them, that the Sept. 11 anniversary plotters journey to jihad began in the U.S., took them to the Afghanistan-Pakistan region in July and had them, according to the CIA informant whose information is the hard bottom of the case, return to the U.S. on Aug. 31 or Sept. 1 to carry out an anniversary bomb plot.

So far, no new intelligence has come in to support or discount the informant's account coming in from overseas.  The process of elimination has been a grueling one for analysts and law officers working around the clock.

Since last Thursday, authorities have feverishly scrubbed communications and travel manifests using a series of computer search formulas to reduce the pool of possible candidates for investigation from several hundred names to a much narrower group, according to law enforcement and intelligence sources.

Now the FBI Joint Terrorism Task Force (JTTF) has fanned out its resources -- which include those of numerous other agencies -- across the country to find, interview and eliminate people from the pool of potential suspects.

Here is how that process works according to authoritative sources who spoke to ABC News' Pierre Thomas:

The pool of names was culled from hundreds of men who flew into the U.S. from south Asia in August.  That list was developed by running names through all terror watchlists and intelligence files available to the U.S. government.

In sifting and narrowing the names, authorities also used a formula that included the ages of potential cell members -- the informant said they would be in their 30s or 40s -- date of travel, and multiple travel routes to and from the Afghan-Pakistan region.  From among that group, multiple authorities have told ABC News that two identities are of particular interest and appear possible members of the plot.

But whether the credible information that there is a plot is ultimately proven or disproved depends on whether an informant's information, gleaned secondhand from conversation in a house in Afghanistan, can be verified.

The specific travel time frame information comes from the same CIA informant who said three people were dispatched by al Qaeda to carry out a bomb plot in either New York or Washington.

Despite the secondhand nature of the source, the high quality of the information led authorities to deem the threat credible, if uncorroborated, and triggered the massive rapid police response in Washington and New York, and the all-hands intelligence community and law enforcement manhunt.

"What's striking about this particular information is its clarity," a senior official told ABC News.  "Usually intelligence comes in bits and pieces and officials have to connect dots.  Here, I'm told, there were no dots to connect, there was so much detail in one place at one time.  It was all laid out.  If it's a plot it is well-planned and there's an intention to go forward with it.  If it turns out not to be real then it's definitely not.  There is no middle ground."

As Americans begin to remember the 9/11 anniversary on Sunday, officials say they have no choice but to act as if the threat is real and the clock is ticking.

"Al Qaeda again is seeking to harm Americans and in particular to target New York and Washington," said Secretary of State Hillary Clinton in New York Friday.  "We are taking this threat seriously.  Federal, state and local authorities are taking all steps to address it."

Police and federal agents have run down stolen vehicles, stopped suspicious trucks, issued "Be On The Look Out's" (BOLOs) for persons suspected of harboring animosity that could be directed at ground zero or the president, on top of continuing the hunt for terror plotters.

The BOLOs were sent for subjects including a 2003 Afghanistan veteran believed armed with handgun and believed to have crossed the George Washington Bridge Saturday morning heading from New Jersey to New York.

That man, missing since Tuesday from his job, had been located in New Jersey by authorities a day earlier, and was the subject of a JTTF BOLO when his EZPass alerted police he had crossed the bridge.

Authorities have also investigated a stolen van on Long Island, a missing rental van near New York, possible stolen vans in Maryland, wiring boxes on bridges, packages and bags left in boroughs outside of Manhattan, airport security breaches at John F. Kennedy International Airport and suspicious packages at Dulles International Airport -- all seen since Friday night and all given extra scrutiny.

In the midst of the scramble Saturday, a Department of Homeland Security analyst sent out a bulletin that multiple sources in law enforcement say erroneously linked a man to the alleged anniversary plot.  That document was rapidly pulled back, but the JTTF in North Carolina continued to be besieged by calls.

"We found out it came from an overzealous DHS analyst.  Charlotte does have a case on him but he is not one of the three.  DHS is going to get spanked.  Charlotte is getting inundated with calls," one official told ABC News.

Copyright 2011 ABC News Radio


Biden on Terror Threat: Credible Source But No 'Smoking Gun'

ABC News(NEW YORK) -- Vice President Joe Biden said Friday that while intelligence on a potential terror plot against New York City or Washington, D.C., came from a credible source, it has been unconfirmed and there is "no certitude" an attack has been planned.

Biden said he and President Obama had been briefed on intelligence developed by the CIA in the last 48 hours that three men may have entered the country with the intent to launch a vehicle-bomb attack on the homeland.

"We do have talk about using a car bomb.  We've been told that was an intention... from a credible source," Biden said on ABC's Good Morning America.  "But we do not have confirmation of that."

"We don't have a smoking gun," he said.

The FBI and Department of Homeland Security sent a bulletin out to law enforcement agencies across the country late Thursday warning against the potential plot by al Qaeda surrounding the 10th anniversary of Sept. 11 to "avenge Osama bin Laden's death."

Although authorities said they had not yet identified the suspects, they are looking at multiple names of individuals who entered the U.S. after mid-August.  The operatives are believed to have embarked on their journey to the U.S. from the tribal areas of Pakistan, according to two senior officials.  One official said the route may have taken them through Dubai.  The threat information was obtained recently and originated from overseas sources -- Pakistan, according to one official.

Intelligence and law enforcement officials told ABC News that at least one of the individuals is a U.S. citizen and one official said that two of the individuals may have had U.S. documentation -- whether green cards or passports was unclear.

The information on the plot was "very specific," said one official, adding, "It seems like the information has been worked for a while."

Officials told ABC News Thursday the alleged terror plot was initiated by new al Qaeda chief Ayman al-Zawahiri, Osama bin Laden's successor, who had pledged to avenge bin Laden's death earlier this year at the hands of U.S. Navy SEALs.

"As we know from the intelligence gathered from the Osama bin Laden raid, al Qaeda has shown an interest in important dates and anniversaries, such as 9/11.  In this instance, it's accurate that there is specific, credible but unconfirmed threat information," Department of Homeland Security spokesman Matthew Chandler said in a statement Thursday.

But while the FBI, CIA and other federal agencies rush to identify the men linked to the potential plot, several officials in addition to Biden emphasized that the information has not been confirmed.

"Credible means this is something they've been expecting, something that could happen," former White House counter-terrorism advisor and now ABC News consultant Richard Clarke said on GMA.  "Unconfirmed means they have one source... Sometimes people make up stories and pass them on to the CIA in great detail."

In New York, police commissioner Ray Kelly announced Thursday evening that police would be deploying additional bomb-sniffing dogs, radiation detection equipment and random vehicle checks beginning Friday morning.  There also will be stepped up bag searches, towing of illegally parked cars and increased police presence on the ferries, Kelly said.

Initially, one official added that at least two rental trucks -- one from Penske and one from Budget -- were being sought nationwide.  Those trucks have since been recovered and appear to have had no connection to the plotters.

In Zawahiri's most recent video, released last month, he called for his followers to focus on the U.S.

"Hunt her down wherever you may encounter her.  Hunt her down to cut what is left of her corruption's tail," Zawahiri says in the video.

"We know from Bin Laden's own handwriting he wanted to do an attack around the anniversary," said Clarke.  "We know from his successor's own audio tapes and video tapes that he feels he has to prove al Qaeda is still alive by avenging bin Laden's death.  And we know that this kind of technique could be relatively easily done, even by an al Qaeda that's on the ropes, even by an al Qaeda that has very few people left."

Copyright 2011 ABC News Radio

ABC News Radio