Osama bin Laden has been killed in a CIA operation in Pakistan, President Obama announced from the White House Sunday, ending a years-long manhunt for the leader of al-Qaeda and architect of the Sept. 11, 2001, attacks on New York City and Washington, according to multiple sources.

The announcement comes about four months before the 10th anniversary of the devastating Sept. 11 attacks on the United States, which were executed by the Al Qaeda network helmed by Bin Laden and prompted the start of a war on terror that has dominated U.S. foreign policy.

Mr. Obama said bin Laden was not a Muslim leader, but a "mass murderer of Muslims." The president said bin Laden was captured with the help of Pakistani intelligence.  Obama said that last week, intelligence had been gathered as to Bin Laden's whereabouts in Pakistan. Earlier Sunday, after a firefight, a "small team of Americans" killed Bin Laden and "took custody of his body." Obama said no Americans were harmed and the team "took care to prevent casualties."

More information is forthcoming.