US military action has lead to the death of Osama Bin Laden. His body is in U.S. custody.
Bin Laden is top of the US most wanted list.
He is accused of being behind a number of atrocities, including the attacks on New York and Washington on 11 September 2001.
UPDATE: Sources say that Bin Laden was killed in a strike today . His identity been confirmed by using DNA samples from a dead relative -possibly his sister.
According to CNN, around 9:30 pm, the major news organizations were informed that the President would be making a statement about national security. According to MSNBC: Will be speaking about a "Serious and grave CIA operation happening overseas."
UPDATE: WASHINGTON (Reuters) - Al Qaeda leader Osama bin Laden was killed at a mansion outside the Pakistani capital Islamabad in a US lead Special Forces operation.
Crowds gathered outside the White House in Washington DC, chanting "USA, USA" after the news emerged.
Bin Laden approved the 9/11 attacks in which nearly 3,000 people died, saying later that the results had exceeded his expectations.
Bin Laden has evaded the forces of the US and its allies for a decade, despite a $25m bounty on his head.
His death will be seen as a major blow to al-Qaeda but also raise fears of reprisal attacks. correspondents say.
President Obama said in his speech to the nation: '"A small team of Americans carried out the operation," Obama said. "After a firefight, they killed Osama bin Laden and took custody of his body."
In a historic moment, Obama described the war against Al Qaeda over the last 10 years since 9/11,
The President described events over the last few weeks when acting on specific intelligence, Obama said he ordered Osama's place of hiding in Pakistan stormed and as a result the raid Osama Bin Laden was killed.
No civilians or US military casualties were reported.
According to sources in Washington, the operation had been in the making for the last 9 or 10 months with tips about the specific place (Abbottabad, Pakistan, where he was killed) as a being one of Bin Laden's safe houses in August of last year.
The fact that it happened inside Pakistan, may have implications that Pakistani intelligence may have been protecting him.
Pakistani officials were not told of the operation until it was well underway in fear that certain persons in the Pakistani government would have tipped-off Bin Laden's security forces.
A Pakistani military garrison is reported as being just down the road from the Bin Laden compound.
Intelligence sources say a small contingency of 30 Navy Seals supported by CIA Predator drones and helicopters covertly converged on the compound in Abbottabad, Pakistan and after a short firefight Osama Bin Laden was shot and killed after firing several shots himself and using one of his couriers ( a woman) as a human shield.
Latest reports say the compound is now on fire and burning to the ground - although there are no US presence on scene.
His body was immediately flown out by US helicopter and his identity confirmed by the CIA using DNA from his dead sister.
Update: Osama Bin Laden was shot in the head at least once by US Navy SEALS, according to NBC news, after what has been described as a brief exchange of gunfire.
President Obama said the location of the Pakistani compound where Bin Laden was hiding was confirmed last week, and he gave to order to proceed with the military operation against Bin Laden on Sunday morning.
The site was described as a mansion inside Abbottabad, Pakistan and once used by the Pakistani military. Two known Bin Laden "couriers" were killed in the raid - who unwittingly were being tracked by the CIA to the compound as was Osama Bin Laden's brother.
One US helicopter was reported damaged during the firefight but no US casualties have been reported.
Former US President George Bush says he has congratulated President Barack Obama after hearing about the death of Osama bin Laden.
In a statement, Bush said Obama called to tell him that US forces had killed bin Laden.
Bush said, ‘‘This momentous achievement marks a victory for America, for people who seek peace around the world, and for all those who lost loved ones on September 11, 2001.’’
Cheering crowds are reported gathering in front of the White House and at Ground Zero in NYC.
The announcement by Obama from the East Room of the White House came eight years to the day after President Bush announced the end of major combat operations in Iraq, the so-called “Mission Accomplished” speech from the aircraft carrier USS Abraham Lincoln.
Members of Congress were briefed on the news by Vice President Joe Biden throughout the weekend, according to a Senate aide.
Sen. Dianne Feinstein, chairwoman of the Senate Intelligence Committee, related the news to mourners at a memorial service for political consultant Kam Kuwata. Feinstein said Obama was announcing it on TV as she spoke. However, she announced the news well before Obama began to speak.
Based on statements given by U.S. detainees, intelligence officials have known for years that Bin Laden trusted one al-Qaida courier in particular and they believed he might be living with him in hiding.
In November, intelligence officials found out where he was living, a huge fortified compound in an affluent suburb of Islamabad. It was surrounded by walls as high as 18 feet high, topped with barbed wire.
There were two security gates and no phone or Internet running into the house.
Intelligence officials believed the $1 million home was custom-built to harbor a major terrorist.
CIA experts analyzed whether it could be anyone else, but time and again, they decided it was almost certainly bin Laden.
Three adult males were also killed in Sunday's raid, including one of bin Laden's sons, whom officials did not name. One of bin Laden's sons, Hamza, is a senior member of al-Qaida.
Obama struck a less than boastful tone in his brief announcement, although he said the death of bin Laden was "the most significant achievement to date in our nation's effort to defeat al-Qaida.
"His death does not mark the end of our effort. There's no doubt that al-Qaida will continue to pursue attacks against us. We must and we will remain vigilant," he added.
Moments after he spoke, American officials cautioned that the events could lead to heightened threats against the United States.
Officials said the U.S. would ensure that bin Laden's body was handled in accordance with Islamic tradition.
Various sources and news agencies contributed to this report.
