At just after 1.15am residents of Abbottabad were woken by shattering explosions. Prolonged bursts of gunfire followed and military vehicles hurtled towards a burning building in a wealthy neighbourhood on the edge of the city.
Killing zone: Map showing where bin Laden was found by US forces
A little later the silhouettes of three helicopters could be seen rising and disappearing into the dark sky. Nearly a decade after 9/11, the hunt for Osama bin Laden was finally over.
The operation which claimed the life of the founder of al-Qaida, and the world's most wanted terrorist, had taken only 48 minutes. Bin Laden had been shot dead.
Four others, including a woman, were also killed. A helicopter which had crashed at the site was blown up by the departing US special forces as they flew off with the bodies.
There had been a brief but fierce firefight with guards on the roof of the house opening up with Kalashnikov assault rifles and rocket-propelled grenades. The downed helicopter may have been damaged in this exchange. Bin Laden was shot twice in the head, his death likely to be viewed as an execution after it emerged Barack Obama had sanctioned a ‘kill option’ to the US Navy Seals carrying out the mission.
Bin Laden's heavily fortified last refuge was only 100 yards from Pakistan's version of Sandhurst, the Kakul Academy, in a city bristling with security facilities.
US officials had little doubt that senior elements within the country's military and intelligence service had been shielding the al-Qaida leader, and had taken every precaution possible to ensure they did not learn how close the Americans were to getting their quarry.
The trail that led to the deaths at Abbottabad started six years ago when two detainees at Guantanamo Bay had provided the nickname for bin Laden's most trusted courier. It took another 12 months to find the man's real name, and it was not until 2009 that it emerged he was based close to Islamabad.
The fact the courier was operating with seeming impunity near the Pakistani capital convinced US officials he had the protection of the ISI, the Pakistani secret police, and reinforced their decision not to share their information with the Pakistanis.
Investigations, mainly reliant on electronic tracking, eventually led them to a residence the courier shared with his brother at Abbottabad. The mansion, set on a hilltop, ringed by 12-feet-high reinforced concrete walls topped with razor wire, had been built in 2005 at a cost of $1m (£600,000), 10 times more than other properties in the area. It did not, however, have either telephone or internet connection — seen as a counter-surveillance measure.
The CIA was convinced the location was for the use of someone extremely important and, for a while, explored the possibility it might be housing Mullah Omar, the former head of Afghanistan's Taliban regime.
But after a month's surveillance the CIA told the President it believed it was, in fact, bin Laden who was staying in the compound.
Two more months of surveillance followed before Mr Obama held the first of five meetings with the National Security Council on March 14.
The last session took place at 8.20am last Friday when, before flying off to inspect flood damage in Alabama, President Obama finally authorised the operation.
It began when a special forces squad took off from the Ghazi airbase in north-west Pakistan. They returned with bin Laden's corpse, which was transferred to another aircraft heading for Afghanistan — where he had first found fame in the US-sponsored war against the Russians.
There, at Bagram airbase, the formalities of identification were concluded, and the man who had been projected as the most dangerous enemy facing the West, was taken on his final journey for burial at sea.
Questions and answers
Q Why did the Americans kill, not capture, Osama bin Laden?
A Security sources in Washington have said the mission was to kill, not capture, bin Laden. But it was widely reported that American special forces asked bin Laden to surrender, but that he refused to do so and was shot in the head. Had the al-Qaida leader been arrested, he would likely have been taken to a high security American prison before being tried for the September 11 attacks and other terrorist atrocities. The process could have taken years.
Q Did any other country take part in the raid?
A No. The operation was undertaken entirely by the United States. It is unclear whether the US gave allies, such as Britain, any advance notice, but it seems clear that Pakistan's intelligence agency, the ISI, was not told until after the raid.
Q Has the US offered any evidence of the death?
A A photograph purporting to show bin Laden's corpse was circulated on the internet yesterday, but quickly dismissed as a fake. The Americans have said that DNA evidence confirmed that the body was that of bin Laden, but so far have offered no evidence. Until photographic evidence, at the very least, is published, yesterday's operation will lead to a plethora of conspiracy theories.
Q Was anyone else killed in the raid?
A Three other people were killed in the attack, including one of bin Laden's adult sons. A courier was also killed, as was a woman.
Q What has happened to bin Laden's body?
A After the raid US troops took the body to an airbase across the border in Afghanistan. Bin Laden is originally from Saudi Arabia, but Riyadh refused a request to take the body, so it was removed from Afghanistan and buried at sea. The advantage is that it leaves no monument for supporters to use as a focal point.
Q Was he treated in line with Islamic tradition?
A According to the Americans, the body was handled in accordance with Islamic tradition. The sea burial has already been criticised by Muslims, however. “They can say they buried him at sea, but they cannot say they did it according to Islam,” said Mohammed al-Qubaisi, the grand mufti in Dubai. “If the family does not want him, you dig a grave anywhere, say the prayers and that's it.”