(OAK CREEK, Wis.) -- Seven people were shot and killed Sunday morning at a Sikh temple in Oak Creek, Wis., in what officials are treating as a case of domestic terrorism.
ABC News confirmed on Monday that the alleged gunman is Wade Michael Page, a 40-year-old Army veteran who served from April 1992 through October 1998.
While police have not given any details on the motive of the shooter, sources have told ABC News the shootings are the work of a "white supremacist" or "skinhead."
Bureau of Alcohol, Tobacco, Firearms and Explosives Special Agent Thomas Ahern said Page had tattoos that suggested he had ties to white supremacists.
"It is being investigated. And what his tattoos signified is being investigated. They are all pieces of a possible puzzle to learn what was his motive in carrying out such a horrific act," Ahern said.
Sunday evening, the FBI and a bomb squad arrived at a home in Cudahy, Wis., near Oak Creek, and ABC News' Milwaukee affiliate WISN-TV reported the action appeared to be related to the temple shootings earlier in the day.
Authorities also were trying to trace a single, semiautomatic handgun recovered at the scene, sources told ABC News.
In addition to the seven confirmed dead, three people -- two adult male civilians and a male police officer -- were in critical condition and were being treated at a local hospital, said officials at Froedtert & The Medical College of Wisconsin. None of the victims have been identified.
The apparent gunman was shot and killed in an exchange of gunfire with the wounded police officer outside the temple and was one of the seven dead.
"The officer stopped a tragic event that could've been a lot worse," Oak Creek Police Chief John Edwards told reporters.
Four people were found dead inside the temple and two others were found dead outside the building. Edwards said authorities were treating the event as a domestic terrorism incident and the FBI would be conducting a full investigation.
"The FBI is working closely with the Oak Creek Police Department and other local and federal agencies to investigate today's shooting incident," FBI Milwaukee Special Agent in Charge Teresa Carlson said in a written statement. "This remains an active investigation in its early stages. While the FBI is investigating whether this matter might be an act of domestic terrorism, no motive has been determined at this time. We know our community has been deeply impacted by this incident, and our thoughts are with those affected and particularly with the officer who was wounded in the line of duty to protect others."
President Obama was told about the shooting around 1 p.m. Sunday and released a statement later in the afternoon.
"At this difficult time, the people of Oak Creek must know that the American people have them in our thoughts and prayers, and our hearts go out to the families and friends of those who were killed and wounded," Obama said. "My administration will provide whatever support is necessary to the officials who are responding to this tragic shooting and moving forward with an investigation.
"As we mourn this loss which took place at a house of worship, we are reminded how much our country has been enriched by Sikhs, who are a part of our broader American family," he added.
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