(NEW YORK) -- Appearing to assume the role as the new leader of al Qaeda, the former number two Ayman al-Zawahiri vowed to avenge the death of Osama bin Laden "blood for blood," in a video posted on the Internet Wednesday morning.
The 28-minute video is the first statement from the 59-year-old al-Zawahiri, an Egyptian doctor, to acknowledge the death of bin Laden, killed in a U.S. Navy SEAL raid into Pakistan last month. Looking aged, and at times angry, al-Zawahiri used a chopping motion with his hands and urged his followers to remember the 9/11 attacks against Americans and made a point to recall the deaths of U.S. military personnel at the Pentagon.
Al-Zawahiri did not specifically mention whether he was now the leader of the terror group's global jihad, but his tone and words suggested he had the legitimacy to succeed bin Laden.
His anger was apparent as he criticized the U.S. for the manner in which bin Laden was reportedly buried at sea from a U.S. Navy aircraft carrier. He called it not Islamic, but "the Islam of the United States, the Islam of Obama."
Elsewhere in the message, in which al-Zawahiri appeared with an automatic rifle to his side, he urged the youth of Pakistan to follow the lead of the youth of Egypt, Tunisia, Libya and Syria in seeking to overthrow the government.
Al-Zawahiri, founder of the Egyptian extremist group Egyptian Islamic Jihad, also helped found al Qaeda with bin Laden. He sports the largest bounty offered for information on any terrorist by the U.S. government -- $25 million -- and is wanted for his role in the 1998 bombings of the U.S. embassies in Tanzania and Kenya, which claimed 224 lives.
Al-Zawahiri made his last video appearance in April in which he discussed the revolt in Libya and called on Libyans to oust dictator Moammar Gadhafi before "Western aid...turns into invasions."
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