UPDATE 2-Al Qaeda Leader Bin Laden Dead - U.S. Officials

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By Mark Hosenball and Jeff Mason

WASHINGTON (Reuters) - Osama bin Laden was killed in Pakistan and his body has been recovered by U.S. authorities, U.S. officials said on Sunday night.

U.S. President Barack Obama was to make the dramatic announcement shortly in a hastily called, late-night appearance at the White House: That the mastermind of the Sept. 11, 2001, attacks was killed in an American-led operation in a mansion outside Islamabad.

It is a major accomplishment for Obama and his national security team, after many Americans had given up hope of ever finding bin Laden.

A crowd gathered outside the White House to celebrate, chanting, "USA, USA."

Obama's predecessor, George W. Bush, had repeatedly vowed to bring bin Laden to justice "dead or alive" for the Sept. 11, 2001, attacks on New York and Washington that killed nearly 3,000 people, but never did before leaving office in early 2009.

U.S. officials said that after searching in vain for the al Qaeda leader since he disappeared in Afghanistan in late 2001, the Saudi-born extremist was killed and his body recovered.

Having the body may help convince any doubters that bin Laden is really dead.

He had been the subject of a search since he eluded U.S. soldiers and Afghan militia forces in a large-scale assault on the Tora Bora mountains in 2001. The trail quickly went cold after he disappeared and many intelligence officials believed he had been hiding in Pakistan.

While in hiding, bin Laden had taunted the West and advocated his militant Islamist views in videotapes spirited from his hideaway.

Besides Sept. 11, Washington has also linked bin Laden to a string of attacks -- including the 1998 bombings of American embassies in Kenya and Tanzania and the 2000 bombing of the warship USS Cole in Yemen. (Writing by Steve Holland; editing by Philip Barbara)