WASHINGTON — Even as the Navy SEALs slid down ropes from their hovering helicopters, there still was some uncertainty that the man they were after was inside the massive, night-shrouded compound on the edge of the sleeping city in northeastern Pakistan.
After all, Osama bin Laden was long thought to be hiding in a cave or other refuge in Pakistan's rugged tribal area bordering Afghanistan.
But one of the raiders thought he recognized the leader of al Qaida, and dropped him with a shot to his left eye as the SEALs stormed into a third-floor room of the main house during a nearly 40-minute firefight.
The raider compared the dead man's face to bin Laden's picture. They seemed to match. So did measurements of his nose, eyes, height and other features. Then one of the dead man's wives positively identified him. Yet it wasn't until later that DNA tests of "99.99 percent confidence" dispelled any lingering uncertainty.
Bin Laden was dead.
"Justice has been done," President Barack Obama declared on national television after he and close aides, who had monitored the operation as it unfolded on the other side of the world, were sure the leader of al Qaida was killed before dawn on Monday, Pakistan time.
"It was probably one of the most anxiety-filled periods of time, I think, in the lives of the people who were assembled here," said John Brennan, Obama's chief counterterrorism adviser, at a White House news conference. "The confidence was building, yet at what point do you feel confident that you have the person you were after?"
No Americans were killed or injured. Four people other than bin Laden died: a trusted courier thought by U.S. officials to have harbored bin Laden and his family for several years; the courier's brother; bin Laden's son, Khaled; and one of the terrorist leader's wives, shot as she shielded her husband.
Details of one of riskiest and meticulously planned covert operations ever pulled off by the CIA and the U.S. military emerged in briefings and interviews Monday with administration, intelligence and military officials after the raid outside the city of Abbottabad. All but Brennan requested anonymity as matter of policy.
The helicopters, flying from Afghanistan in the dark, had to operate undetected in one of Pakistan's densest air defense zones, evading radars and missile batteries protecting the capital, Islamabad, and the adjacent military headquarters city of Rawalpindi.
One helicopter developed a mechanical failure and crashed outside the compound's towering walls. It was blown up before the raiders departed so its top-secret equipment couldn't be captured. Pakistani jets scrambled, but not until the SEALS were long gone with bin Laden's corpse.
"We weren't detected coming in and going out. Even the helicopter crashed, and we blew it up," said a U.S. official. "We did not encounter Pakistani forces at any time.
Two women in the compound were injured and treated at a military hospital, said two Pakistani officials, who asked not to be further identified. One was believed to be another bin Laden wife, the one who identified his body, and the other a daughter.
Before leaving, the SEALs swept up computer hard drives and other materials that intelligence analysts are now scouring for the identities and whereabouts of other al Qaida operatives, and other information that can be used to fight the terrorist network, U.S. officials said.
Only bin Laden's corpse was removed, flown to a U.S. aircraft carrier in the northern Arabian Sea.
After samples were taken for DNA testing, it was washed in private by two Muslim members of the U.S. military, wrapped in a white sheet, placed in a weighted bag and slid into the water from the deck of the USS Carl Vinson to the recitation of "religious remarks" by a U.S. officer that were translated into Arabic, officials said. They insisted that all was in accordance with Islamic practice.
The accounts left critical questions unanswered. Perhaps the most significant: Did anyone in the Pakistani army, which has ruled the country for more than half of its 64 years of independence, or the powerful spy agency linked to groups allied to al Qaida, the Inter-Services Intelligence, help harbor bin Laden or know of his presence?
"I think it is inconceivable that bin Laden did not have a support system in the country that allowed him to remain there for an extended period of time," Brennan said.
Pakistan's premier military academy is a mile from the compound, and the area is home to numerous retired senior officers and two infantry regimental headquarters.
Moreover, the ISI used the area — until it stopped under U.S. pressure in 2004 — to recruit and train Islamic militants that it dispatched to fight on India's side of the disputed Kashmir region, said Thomas Lynch, a retired U.S. army colonel who's now a research scholar at the National Defense University in Washington.
"There is no way that ISI couldn't have known about this," Lynch said. "You can't throw a dead cat in that town and not hit a military or an ISI active or alumnus."
Only U.S. personnel participated in the operation, and Obama's decision last Friday to launch it wasn't shared with any other country, including Pakistan, which was informed only after the helicopters had left its airspace.
CIA Director Leon Panetta oversaw the operation from a special command center in his 7th floor conference room at CIA headquarters outside Washington. Obama and the small circle of advisers who were aware of the operation convened in the White House Situation Room.
Operational command was turned over to the SEALs commander once the "go order" for the raid was given, a U.S. official said.
The compound was detected after years of effort in which CIA analysts doggedly pieced together leads on members of bin Laden's inner circle, including his couriers. Some of their names came from al Qaida members at Guantanamo.
"One courier in particular had our constant attention," said a senior administration official, who declined to release the name. He described the courier as a "protege" of Khalid Sheikh Mohammed, the alleged architect of the 9/11 attacks who was captured in Pakistan in March 2003 and is being held at Guantanamo.
The CIA positively identified the courier four years ago and two years ago identified areas of Pakistan where the courier and his brother operated. Because they used tight operational security, the agency didn't pinpoint their residence until August.
The courier and his brother were tracked to the palatial compound built in 2005 at the end of a dirt road in an isolated suburb, said a second senior administration official. He added that it was believed that the residence was constructed specifically for bin Laden.
Numerous details of the structure helped bolstered intelligence analysts' belief that it housed a "high value terrorist."
The triangular compound occupies about an acre of ground in a largely agricultural setting. It is about eight times larger than any nearby homes, and is surrounded by 12- to 18-foot walls topped by barbed wire. Different sections of the structure were walled off from each other.
In aerial photographs and a drawing released by the U.S. government, there is a three-story main home, and a smaller residence, along with several other buildings.
Bin Laden and his family occupied the second and third floors of the main house, whose top story is encased by a "seven-foot privacy wall" to shield the occupants, U.S. officials said.
The "extraordinary security measures" also included two electrified security gates at either end of a long, walled entry passage from the street. Trash was burned inside the compound before being taken out for disposal, they said.
The compound cost an estimated $1 million — a large sum in impoverished Pakistan — yet it had no telephone or Internet connections.
The courier and his brother "had no explainable source of income," said the second administration official, who added that "we soon learned that more people were living at the compound" than just the two men and their families.
CIA analysts, working with the eavesdroppers of the National Security Agency and experts at the U.S. Geospatial Intelligence Agency, which analyzes satellite imagery, concluded "with strong probability" that a third family — bin Laden and several family members — also were living there, he said.
The compound's massive security, its isolated location and its size "was consistent with what our experts had expected bin Laden's hideout would look like," he continued. "No other candidate fit the bill as well as bin Laden did."
Months of planning went into the helicopter-borne operation, said a third senior administration official, who declined to provide many details, including how many personnel and aircraft participated.
The SEALs practiced the operation numerous times on a full-scale mock-up of the facility at an undisclosed location.
"Needless to say, when they hit the compound, they had already trained against it numerous times," Brennan said. "The outer features of the compound were studied intensely, and there were certain assessments made about where individuals were living and where bin Laden and his family were."
Obama met with a close circle of top aides five times since March 14 to review the intelligence assessment and operational plans before giving the final go-ahead.
There was extensive debate about whether the compound should be bombed or U.S. commandos sent in, the option embraced by Obama and a majority of his aides, Brennan said.
Obama's top lieutenants met on Sunday around noon in the White House Situation Room, and the president joined them in the early afternoon, left and then returned when the operation began, he said.
"The minutes passed like days, and the president was very concerned about the security of our personnel," Brennan recounted. "It was clearly very tense, a lot of people holding their breath, and there was a fair degree of silence as it progressed as we would get updates. And when we finally were informed that those individuals who were able to go in that compound and found an individual they believed was bin Laden, it was a tremendous sigh of relief that . . . who we believed was in that compound actually was . . . found."