| NEW YORK
NEW YORK Almost immediately after the United States said it had killed al Qaeda leader Osama bin Laden in Pakistan, the conspiracy theories started.
Even some relatives of the September 11 victims of the 2001 attacks on America say his death, announced by President Barack Obama in a speech at the White House, begs questions.
The U.S. government said Bin Laden was shot in the head when elite Navy SEALS stormed his compound on Monday after he had evaded a decade-long manhunt as the world's most wanted man.
But his swift burial at sea, in which he was slipped into the Arabian Sea in a weighted body bag, and authorities' reluctance to release pictures of his corpse have been fuel for the conspiracy theorists.
One hotly argued assertion is that bin Laden was in fact a CIA stooge who had been dead for years, a fanciful figure who was used to justify America's war in Afghanistan.
That is a position shared by U.S. anti-war activist Cindy Sheehan and other doubters from Indiana to Kabul.
"If you believe the newest death of OBL, you're stupid," Sheehan wrote on her Facebook page.
Sheehan, who set up an anti-war camp at President George W. Bush's Texas ranch in 2005, disputes the facts given by the government, asking how the United States could get such fast DNA results, why the burial was hasty and why no video had been released.
And, she noted, the late Pakistani President Benazir Bhutto claimed in 2007 that bin Laden was already dead.
Sheehan is not alone in posing such questions.
Internet site Yahoo said searches for "osama bin laden not dead," "osama bin laden still alive" and "bin laden not dead" spiked off the charts on Monday.
Men were most likely to think he may be alive, Yahoo said, adding that searchers of "bin laden conspiracy" were mostly from Oregon, Wisconsin, North Carolina, Indiana and New Jersey.
In Iran, the semi-official Mehr news agency declared: "The death of Osama is a lie."
Iranian state television news said by disposing of the body at sea, "the mystery (of his death) has increased." Iranian media say the myth of bin Laden has been used to justify the U.S. occupation of its neighbor, Afghanistan.
Nearly 3,000 people died when planes hijacked by bin Laden's al Qaeda followers flew into the World Trade Center, the Pentagon and a field in Pennsylvania on September 11, 2001, setting off a hunt for the plot's architect.
Afghanistan's Taliban said in a statement posted on their website that talk of bin Laden's death was "premature" and that the United States had not provided "convincing evidence."
ELVIS AND ALIENS
Some Americans thrive on conspiracy theories. Who really shot President John F. Kennedy? Elvis Presley lives! Did aliens land in a UFO in Roswell, New Mexico? Was September 11 orchestrated by U.S. interests to justify the wars in Afghanistan and Iraq?
At New York's "Ground Zero" where the twin towers once stood, some visitors pondered whether bin Laden's death might be too good to be true.
"I just hope we really did get him. They buried him at sea. Who knows what happened?" said project manager Sal Leto, 59.
Retired teacher Joani Ellingson, 62, who was visiting from Minnesota, said: "It is part of the death culture that we want to see proof positive. We have a curiosity."
Rosaleen Tallon, whose brother died in the attacks on the World Trade Center, said she was "dismayed" that bin Laden was buried so quickly.
"It has unfortunately opened this up to the possibility of conspiracy theories," she said.
At Pace University, political science professor David Caputo asked students if they doubted bin Laden was dead. Two thirds had at least a slim doubt, and 5 percent had a major doubt, he said.
(Additional reporting by Ramin Mostafavi in Tehran and Edith Honan in New York; editing by Christopher Wilson)