Barack Obama and Hilary Clinton watch as US forces raid bin Laden's Pakistan compound in real time. This photo was posted via The White House’s Flickr account after bin Laden's death was officially announced, attracting a huge one million views in just 25 hours.
Al Qaeda has confirmed the death of its leader Osama bin Laden and vowed to launch revenge attacks on the US and its allies.
A statement posted on jihadist websites warned that happiness over the terror chief's demise would soon be turned on its head.
The group described itself as a "curse" on America, promised bloodshed and also called on Pakistan to rise up in revolt.
An audiotape purporting to be of bin Laden speaking a week before his death is set to be released shortly.
The authenticity of the statement is not possible to confirm independently but it was posted on sites known to be used by the group.
It said: "The mujahid Shiekh Abu Abdullah, Osama bin Mohammed bin Laden, God have mercy on him, was killed on the path taken by those before him and will be taken by others after him. Congratulations to the Islamic umma for the martyrdom of its son Osama.
"We stress that the blood of the holy warrior sheik, Osama bin Laden, God bless him, is precious to us and to all Muslims and will not go in vain.
"We will remain, God willing, a curse chasing the Americans and their agents, following them outside and inside their countries.
"Soon, God willing, their happiness will turn to sadness. Their blood will be mingled with their tears.
"We call upon our Muslim people in Pakistan... to rise up and revolt to cleanse this shame that has been attached to them by a clique of traitors and thieves ... and in general to cleanse their country from the filth of the Americans who spread corruption in it."
The statement also urged the US to treat the bodies of those killed in the raid to be treated with care and returned to their families.
"We warn the Americans not to harm the corpse of the sheikh or expose it to any indecent treatment or to harm any members of his family, living or dead, and to deliver the corpses to their families," it said.
"Any harm done will open the doors of evil upon you doubly, and you will not have anyone but yourselves to blame."
This appears to have been written without knowing bin Laden's corpse was buried at sea within 24 hours of his death.
The announcement paves the way for al Qaeda to name a successor to bin Laden, with his deputy Ayman al-Zawahiri the most likely candidate.
Evidence gathered from bin Laden's compound suggests al Qaeda was already planning an attack on the US rail network to mark the 10th anniversary of 9/11.
Handwritten notes outlined a plot to tamper with a track so that a train would fall into a valley or off a bridge, the joint FBI and Homeland Security bulletin said.
Fox News cited a source as saying the plan was more aspirational than concrete and mentioned services in New York, Washington DC and Chicago.
"We have no information of any imminent terrorist threat to the US rail sector, but wanted to make our partners aware of the alleged plotting," Department of Homeland Security spokesman Matthew Chandler said.
Mr Obama is due to meet the Navy Seals involved in the operation at an army base in Kentucky later on Friday amid ongoing questions about the raid.
UN human rights investigators have demanded full disclosure of the facts, in particular whether they was no intention to take bin Laden alive.
He was not armed when he was shot in the head and chest and it has now emerged only one of the other men in the compound had a gun.
The UN said deadly force could exceptionally be used against terrorists but that they should usually be dealt with as criminals under normal judicial rules.
Hundreds of Pakistanis demonstrated after Friday prayers to condemn the US raid on their soil, shouting "death to America".
Around 1,000 men gathered for a rally in Abbottabad, where bin Laden had been living with his family, with tyres set alight and the US flag burned.
There is intense anger that America launched a raid to capture or kill the terror chief without giving any warning to Pakistan.
It has added to fury at the US presence in the country since the Afghan war and its drone attacks in the north-western tribal areas.
Tensions were further raised by a US drone attack on a vehicle and compound in North Waziristan on Friday morning.
Fazalur Rehman, a labourer, said: "People become terrorists when they see their loved ones killed in drone attacks. Pakistanis simply hate Americans."
Protests were also held on Friday in Quetta, Multan and in other countries.
In Central Java, Indonesia, around 100 Muslims took an oath declaring themselves ready to die as a martyr to avenge the terror chief's death.
Muslims in the Philippines tried to march on the US embassy but were blocked by riot police.
Another revelation set to anger Pakistan is the claim CIA agents had been watching bin Laden from a safehouse in Abbottabad.
Its intelligence-gathering was so exhaustive the organisation asked Congress to reallocate tens of millions of dollars to fund it.
One of bin Laden's wives has claimed she moved into the compound six years ago but it is not clear whether the leader was there for so long.
Pakistan's army has admitted to "shortcomings" in its failure to find him but has warned it will review relations with the US if there are more secret raids.