United States President Barak Obama has officially announced that the al Qaeda leader, Osama bin Laden is dead.
In a televised address late on Sunday evening, the President confirmed Bin Laden had been killed in "firefight" at a mansion outside the Pakistani capital Islamabad in a US-led operation and that his body had been recovered by the US authorities.
Bin Laden approved the 9/11 attacks in which nearly 3000 people died, saying later that the results had exceeded his expectations.
He evaded the forces of the US and its allies for a decade, despite a US$25 million bounty on his head.
In his address, President Obama outlined the steps that had led to the identification of the al Qaeda leader's hiding place.
He said he had given the go-ahead for the operation last week after being briefed in August 2010 on a possible lead to his whereabouts. On Sunday a small team of Americans undertook the operation in Abbottabad, north of Islamabad.
The president said there had been no US casualties and that efforts had been made to ensure there were no civilian casualties.
US officials later said three other people were killed - one,the son of the al Qaeda leader.
A BBC correspondent in Pakistan, Aleem Maqbool told Checkpoint details of the operation were sketchy but eyewitnesses in Abbotabad had said that, late on Sunday evening, they had been told not to go outside. They then heard a helicopter overhead and gunfire.
They said that two women of Arab origin had been taken to hospital and one had subsequently died.
The residents said they did not know who was living at the mansion, which had very high walls, and that they were not allowed to go near it.
Raid lasted less than an hour
A senior US official, giving more detail of the raid to the BBC, said a small US team had conducted the raid in about 40 minutes.
One helicopter was lost due to "technical failure". The team destroyed it and left in its other aircraft.
Three other men were killed in the raid - one of Bin Laden's sons and two couriers - the official said, adding that one woman was also killed when she was used as "a shield" and two other women were injured.
The US official said that intelligence had been tracking a "trusted courier" of Bin Laden for many years. The courier's identity was discovered four years ago, his area of operation two years ago and then, last August, his residence in Abbottabad was found, triggering the start of the mission.
The size and complexity of the structure in Abbottabad had "shocked" US officials, the BBC reports.
It had massive walls 4m to 6m thick and was eight times larger than other homes in the area, according to the BBC.
President Obama says "justice is done"
The US President acknowledged the assistance of Pakistani counter-intelligence in the operation and said that justice had been done.
But he also acknowledged that there could be reprisals in response to Bin Laden's death.
"There is no doubt that al Qaeda will continue to pursue attacks against us," he said. "We must and will remain vigilant at home and abroad."
Reuters reports the US has put its embassies around the world on alert, warning Americans of the possibility of al Qaeda reprisal attacks.
The President also reaffirmed that the US was not at war with Islam.
"I've made clear just as President Bush did shortly after 9/11 that our war is not against Islam. Bin Laden was not a muslim leader, he was mass murderer of Muslims. So his demise should be welcomed by all who believe in peace and human dignity."
US "got lucky "
Ex CIA veteran Michael Scheuer says US intelligence "got lucky" in their operation on Sunday that saw the death of Osama Bin Laden.
Mr Scheuer - who at one stage was head of the Osama bin Laden unit at the CIA told Checkpoint that the al Qaeda leader was in this instance outside the border area where people were less prone to protect him. "Apparently we were able to acquire someone who gave us a hint of his location, and the rest is history."
Death of Osama Bin Laden will not bring brother back
A woman whose brother was killed in theWorld Trade Centre attack in New York on 11 September 2001 says the death of Osama Bin Laden will not bring her brother back.
Myrna Bethke's is a member of the group September 11th Families for Peaceful Tomorrows.
She told Checkpoint she was asleep on Sunday evening when someone sent her a text and she then watched the news.
She says part of her feels a measure of relief but there is also the knowledge that 9/11 will never be over.
She feels it would have been more satisfying if Osama Bin Laden had been taken prisoner rather than killed: "...then there would be a way to talk with him and see what brought this all about ...but his death means that can't happen."
As news of Osama bin Laden's death emerged, joyous crowds descended on the White House and spontaneously erupted with chants of "USA, USA".
Some brandishing national flags, they punched the air and sang the US national anthem, The Star Spangled Banner, even before the announcement of his death by the President.
There were also celebrations in New York
Although it was after midnight, crowds gathered in the Times Square area and at Ground Zero - the site in lower Manhattan where the Twin Towers stood until 11 September 2001.
Many shouted "bin Laden is dead, bin Laden is dead."
The mayor of New York Michael Bloomberg says he hopes the dramatic killing of Osama bin Laden will comfort those who lost loved ones in the 9/11 attacks in New York and Washington.
Former president welcomes death of his nemesis
Former President George W. Bush, who was in office at the time of the Sept. 11 attacks and famously said he wanted Osama bin Laden dead or alive, said on Sunday the death of the al Qaeda leader was a "momentous achievement."
"The fight against terror goes on, but tonight America has sent an unmistakable message: No matter how long it takes, justice will be done," he said in a statement.
Mr Bush's two terms were dominated by what was called a war on terror against Bin Laden's al Qaeda network.
When Barack Obama won the presidency, he offered a new beginning in relations with the Muslim world in a 2009 speech.
But Bin Laden, who was widely assumed to be hiding in Pakistan, dismissed the speech as sowing seeds for hatred and revenge against America.
With his death, the focus may well now shift to the Egyptian-born doctor and surgeon Ayman al-Zawahri, who has been one Al Qaeda's most public figures, repeatedly denouncing the United States and its allies in video messages.
He is the organisation's second-in-command and expected to succeed bin Laden.