WASHINGTON (AP) — President Barack Obama says the United States has conducted an operation that’s killed Osama bin Laden, the mastermind behind the Sept. 11 attacks.

Speaking from the White House in a late night address, Obama said a small team of Americans launched a targeted operation that he approved. He said no Americans or civilians were killed. Bin Laden’s body was retrieved after a brief firefight.

Obama says intelligence showed bin Laden had been located at a compound in Pakistan.

The president said the operation marks the most significant achievement so far against al-Qaida. But Obama said the U.S. must and will remain vigilant at home and aboard.

Outside the White House, a jubilant crowd gathered as word spread of bin Laden’s death.

Copyright 2011 The Associated Press.

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