New video footage of Osama bin Laden has been released, apparently showing him rehearsing for some of his taped messages.
The videos were seized by US special forces when they killed bin Laden in a raid on his compound in Pakistan last weekend.
One US official said the information retrieved represented the largest trove of intelligence ever obtained from a single terrorism suspect.
‘He was far from a figurehead, he was an active player,’ the official told a briefing at the Pentagon.
The large collection included digital, audio and video files, printed material, computer equipment, recording devices and handwritten documents, he said.
Five videos - with the audio removed - were made public including an extraordinary one in which the al-Qaeda chief is seen holding a remote and sitting with a blanket over him, watching images of himself on television in a spare-looking room.
The killing of bin Laden will not deter al-Qaeda and its allies will keep targeting the West, according to US Homeland Security Secretary Janet Napolitano.
As a result, the United States must remain ‘ever vigilant’, Ms Napolitano said.
However she added that the US government had not formally raised alert levels in its National Terrorism Advisory System since bin Laden was targeted at a compound in Pakistan nearly a week ago.
‘What that means is that we have no specific, credible intelligence right now that would indicate that we do so. But we are constantly, with our intelligence partners feeding into us, evaluating that posture,’ she said.
Bin Laden in Pakistan 'over seven years'
Senior Pakistani security officials have said Osama bin Laden may have lived there for over seven years before being shot dead by US forces.
One of Bin Laden's widows told Pakistani investigators that the world's most wanted man stayed in a village for nearly two-and-a-half years before moving to the nearby garrison town of Abbottabad, where he was killed.
His wife, Amal Ahmed Abdulfattah, told investigators earlier that bin Laden and his family had spent five years in Abbottabad, before one of the world's most elaborate and expensive manhunts ended there on Monday.
‘Amal told investigators that they lived in a village in Haripur district for nearly two-and-a-half years before moving to Abbottabad at the end of 2005,’ one of the security officials told Reuters on condition of anonymity.
Abdulfattah, along with two other wives and several children, were among 15-16 people detained by Pakistani authorities at the compound after the raid.
Pakistan, heavily dependent on billions of dollars of US aid, is under heavy pressure to explain how Bin Laden could have spent so many years undetected a few hours drive from its intelligence headquarters in the capital.
Suspicions have deepened that Pakistan's pervasive Inter-Services Intelligence (ISI) spy agency, which has a long history of contacts with militant groups, may have had ties with Bin Laden - or at least some of its agents did.
Pakistan has dismissed such suggestions and says it has paid the highest price in terms of human life and money supporting the US war on militancy launched after Bin Laden's followers staged the 11 September 2001 attacks on America.
