"This is the largest cache of intelligence derived from the scene of any single terrorist," national security adviser Tom Donilon told NBC's "Meet the Press. "It's about the size, the CIA tells us, of a small college library."
Last week, Navy SEALs raided bin Laden's compound in Pakistan and killed him and buried his body at sea. Video seized from the raid has already shown that the world's most wanted terrorist was actively involved in planning and directing al Qaeda's plots.
The U.S. Department of Defense released five videos Saturday showing bin Laden in propaganda tapes. A less-than-flattering video showed the 54-year-old terrorist seated on the floor, watching television while wrapped in a wool blanket and wearing a knit cap.
The evidence seized during the raid includes phone numbers, computer disks and handwritten notes that officials hope will help break the back of the organization behind the 9/11 terrorist attacks. A task force headed by the CIA is working through the material, combing it round the clock to find clues to plots that might already be under way.
In an interview that aired Sunday night, President Barack Obama pointed no fingers, but raised more suspicions about Pakistan.
"We think there had to be some sort of support network for bin Laden inside Pakistan, but we don't know who or what that support network was," the president said. "We don't know whether there might have been some people inside of government, people outside of government, and that's something we have to investigate."
A senior Pakistani official told ABC News, "Elements of Pakistani intelligence - probably rogue or retired - were involved in aiding, abetting and sheltering the leader of al Qaeda."
The U.S. said Sunday that it wants to talk to bin Laden's three widows who are in Pakistani custody.
Donilon said information from them could help answer questions about whether Pakistani authorities helped hide bin Laden while he was on the run.
Bin Laden's youngest wife told officials that the compound where he was killed was not his only hideout over the last few years. She said bin Laden also lived in a small farming village in northern Pakistan, about 260 miles away from the town where he was finally discovered. He was apparently at that small village for about 2 1/2 years.
In Abbottabad, the town where bin Laden was killed, locals say they're skeptical about the authenticity of the videos released by the U.S.
One man said the person in the videos doesn't look like bin Laden or have the same mannerisms. Another person said Washington faked bin Laden's death to create an excuse to withdraw U.S. troops from the region.
In fact, 66 percent of Pakistanis do not believe bin Laden is dead.
The Associated Press contributed to this report.