Osama bin Laden was unarmed when U.S. special forces shot and killed him

(Reuters) - Osama bin Laden was unarmed when U.S. special forces shot and killed him, the White House said, as it tried to establish whether its ally Pakistan had helped the al Qaeda leader elude a worldwide manhunt.

Pakistan faced national embarrassment, a leading Islamabad newspaper said, in how to explain that the world's most-wanted man was able to live for years in the military garrison town of Abbottabad, just north of the capital.

Islamabad vehemently denies it gave shelter to bin Laden.

"There is an intelligence failure of the whole world, not just Pakistan alone," Prime Minister Yusuf Raza Gilani told reporters in Paris. "(If there are) ... lapses from the Pakistan side, that means there are lapses from the whole world."

The revelation that bin Laden was unarmed contradicted an earlier U.S. account that he had participated in a firefight with the helicopter-borne American commandos.

Al Arabiya television went further, suggesting the architect of the 9/11 attacks was first taken prisoner and then shot.

"A security source in the Pakistani security quoted the daughter of Osama bin Laden that the leader of al Qaeda was not killed inside his house, but had been arrested and was killed later," the Arabic television station said.

White House spokesman Jay Carney on Tuesday cited the "fog of war" -- a phrase suggested by a reporter -- as a reason for the initial misinformation.

Bin Laden's killing and the swift burial of his body at sea have produced some criticism in the Muslim world and accusations Washington acted outside international law.

"The Americans behaved in the same way as bin Laden: with treachery and baseness," Husayn al-Sawaf, 25-year-old playwright said in Cairo. "They should've tried him in a court. As for his burial, that's not Islamic. He should've been buried in soil."

But there has been no sign of mass protests or violent reaction on the streets in south Asia or the Middle East, where Islamist militancy appears to have been eclipsed by pro-democracy movements sweeping the region.

Washington will weigh sensitivities in the Muslim world when it decides whether to release photographs of bin Laden's body which could provide proof for skeptics of his death.

Bin Laden was shot in the head. "It's fair to say that it's a gruesome photograph," Carney said. "I'll be candid. There are sensitivities here in terms of the appropriateness of releasing photographs."

Pakistan has welcomed bin Laden's death, but its foreign ministry expressed deep concerns about the raid, which it called an "unauthorized unilateral action."

The CIA said it kept Pakistan out of the loop because it feared bin Laden would be tipped off, highlighting the depth of mistrust between the two supposed allies.

U.S. helicopters carrying the commandos used radar "blind spots" in the hilly terrain along the Afghan border to enter Pakistani airspace undetected in the early hours of Monday.

The Pakistani newspaper Dawn compared the latest humiliation with the admission in 2004 that one of the country's top scientists had sold its nuclear secrets. "Not since Abdul Qadeer Khan confessed to transferring nuclear technology to Iran and Libya has Pakistan suffered such an embarrassment," it said.

The streets around bin Laden's compound in Abbottabad remained sealed off on Wednesday, with police and soldiers allowing only residents to pass through.

"It's a crime but what choice are you left with if I'm not handing over your enemy who is hiding in my house?" said Hussain Khan, a retired government official living nearby, when asked about the apparent violation of Pakistan's sovereignty. "Obviously you will go and get him yourself."

UNARMED RESISTANCE

Carney insisted bin Laden resisted when U.S. forces stormed his compound in the 40-minute operation. He would not say how.

"There was concern that bin Laden would oppose the capture operation and, indeed, he resisted," Carney said. "A woman ... bin Laden's wife, rushed the U.S. assaulter and was shot in the leg but not killed. Bin Laden was then shot and killed. He was not armed."

White House counter-terrorism chief John Brennan, briefing reporters earlier this week, had indicated bin Laden was armed. "He was engaged in a firefight ... and whether or not he got off any rounds, I quite frankly don't know," he said.

The New York Times quoted officials as saying commandos did not know if bin Laden or others were wearing suicide belts.

The strike team opened fire in response to "threatening moves" as they reached the third-floor room where they found bin Laden, CIA Director Leon Panetta told PBS television.

"The authority here was to kill bin Laden," he said. "And obviously, under the rules of engagement, if he had in fact thrown up his hands, surrendered and didn't appear to be representing any kind of threat, then they were to capture him. But they had full authority to kill him."

A U.S. security official had told Reuters on Monday bin Laden would have been taken alive if he had surrendered, but otherwise the raid was a "kill operation."

U.S. officials have also backtracked on an earlier statement that bin Laden's wife had been used as a human shield.

UNLAWFUL KILLING?

U.S. Attorney General Eric Holder defended the action as lawful on Tuesday, but some in Europe said bin Laden should have been captured and put on trial.

"It was quite clearly a violation of international law," former West German Chancellor Helmut Schmidt told German TV. "The operation could also have incalculable consequences in the Arab world in light of all the unrest."

Geoffrey Robertson, a prominent London-based human rights lawyer, said the killing "may well have been a cold-blooded assassination" that risked making bin Laden a martyr.

Pakistan has come under intense international scrutiny since bin Laden's death, with questions on whether its security agencies were too incompetent to catch him or knew all along where he was hiding, and even whether they were complicit.

The compound where bin Laden had been hiding -- possibly for as long as five or six years -- was close to Pakistan's military academy in Abbottabad, about 40 miles from Islamabad.

"It would be premature to rule out the possibility that there were some individuals inside of Pakistan, including within the official Pakistani establishment, who might have been aware of this," Brennan said.

PAKISTAN UNDER PRESSURE

CIA Director Panetta, in an unusually blunt interview with Time magazine, explained why Islamabad was not informed of the raid until all the helicopters carrying the U.S. Navy SEALs -- and bin Laden's body -- were out of Pakistani airspace.

"It was decided that any effort to work with the Pakistanis could jeopardize the mission: they might alert the targets," Panetta said.

Pakistani President Asif Ali Zardari defended his government, which receives billions of dollars in U.S. aid, and blamed "baseless speculation" in the U.S. press.

Pakistan's foreign ministry said its Inter Services Intelligence (ISI) spy agency had been sharing information about the compound with the CIA and other friendly intelligence agencies since 2009 and had continued to do so until mid-April.

In Afghanistan, the Taliban, who harbored bin Laden until they were overthrown in late 2001, challenged the truth of his death, saying Washington had not provided "acceptable evidence to back up their claim" that he had been killed.

(Additional reporting by Reuters bureau worldwide; Writing by Alex Richardson and Nick Macfie; Editing by Dean Yates, John Chalmers and David Stamp)