Obama calls for Pakistani investigation on Bin Laden

Obama told CBS show 60 Minutes the government in Islamabad had to find out if any of its officials knew of the al-Qaeda leader's whereabouts, as Pakistan has consistently denied knowing that Bin Laden was hiding out in Abbottabad.

In an interview aired on Sunday, Obama said the al-Qaeda leader must have had "some sort of support network" in Pakistan, but he did not know whether it included government officials.

"We don't know whether there might have been some people inside of [Pakistan's] government, people outside of government, and that's something that we have to investigate and, more importantly, the Pakistani government has to investigate," the US president said in the interview, which was conducted on Wednesday.

Meanwhile, US National Security Adviser Tom Donilon meanwhile told NBC that Pakistan needs to determine how Bin Laden managed to live for six years just a short drive from the capital and right next to a military academy.

With Bin Laden dead, there has been speculation about whether his deputy, Ayman al-Zawahiri, will take over as al-Qaeda leader. But Donilon said the Egyptian "is not anywhere near the leader that Osama Bin Laden was".

He also said the Pakistani authorities needed to provide the US with access to Bin Laden's three widows, who were taken into custody after last week's US commando raid.

American officials have meanwhile been poring over computer files seized by US special forces from the hideout.

"It's [the intelligence cache] about the size, the CIA tells us, of a small college library," said Mr Donilon.

On Saturday, the Pentagon released from the material five home videos featuring Bin Laden, with the audio removed.

They included a message by the al-Qaeda leader to the US and footage of Bin Laden watching an item about himself on TV.