US President Barack Obama pressed Pakistan on Sunday to probe how Osama bin Laden managed to live for years under the nose of its military, saying he must have been supported by locals.
Obama stopped short of saying the Pakistani government was involved, but the White House called on Islamabad to help counter growing mistrust by granting US investigators access to three of bin Laden's widows who are in Pakistani custody and could have vital information on Al Qaeda.
"We think that there had to be some sort of support network for bin Laden inside of Pakistan," Obama told the CBS show "60 Minutes" in speaking on the matter for the first time.
"But we don't know who or what that support network was. We don't know whether there might have been some people inside of government, people outside of government, and that's something that we have to investigate and, more importantly, the Pakistani government has to investigate."
But one week after an elite team of Navy SEALs killed the Al-Qaeda leader, senior US officials said they had no proof Islamabad knew about his hideout.
The fact that bin Laden was "hiding in plain sight," as the White House described it, for the past five years in a garrison city less than a mile from a top military academy and only 35 miles (56 kilometers) from Islamabad, has deeply strained ties.
Outraged US lawmakers have voiced suspicion that elements of Pakistan's military intelligence services must have known his whereabouts, and are demanding that billions of dollars in American aid be suspended.
A valuable horde of data, including video, digital and audio files, printed items, computer equipment, recording devices and handwritten documents was seized in the raid, an intelligence haul White House National Security Adviser Tom Donilon said was about the size of a "small college library."
With the treasure trove of files and documents in US hands, "we've got a chance to, I think, really deliver a fatal blow to this organization, if we follow through aggressively in the months to come," said Obama.
"We anticipate that it can give us leads to other terrorists that we've been looking for a long time, other high-value targets."
In the final audio tape bin Laden recorded before being killed, he warned there would be no security for the United States until Palestinians can live in security, according to an extremist website.
"America will not be able to dream of security until we live in security in Palestine," bin Laden warned in a message posted on Shamikh1.net, a conduit for Al-Qaeda communications.
"It is unfair that you live in peace while our brothers in Gaza live in insecurity... Accordingly, and with the will of God, our attacks will continue against you as long as your support for Israel continues."
Al-Qaeda has acknowledged bin Laden's death -- and vowed to avenge it -- but no successor has been announced and debate is now swirling over who might take the reins of the terror network.
Donilon said the United States was focusing its attention on bin Laden's longstanding deputy, the Egyptian Ayman al-Zawahiri.
"Zawahiri will be the next number one terrorist that we're looking for in the world," he told NBC television's "Meet the Press."
Reportedly last seen in October 2001 in eastern Afghanistan, close to the lawless tribal regions along the Pakistan border, Zawahiri has released several videos from hiding in which he called for war on the West.
Pakistan's military has hit back at the allegations, demanding that the United States cut its troop presence in the country to a "minimum" and threatening to review cooperation if a similar unilateral raid is conducted.
US officials have stopped short of directly accusing the Pakistanis, but one recent senior political figure who was freer to express her opinions now that she is out of government warned against such "bluster."
"The idea that he could be in a suburb, essentially, of Islamabad is quite remarkable," Condoleezza Rice, who was secretary of state under president George W. Bush from 2005 to 2009, told ABC's "This Week."
"And so Pakistan has some very hard questions to answer, and this isn't a time for bluster from Pakistan."
Pakistan's ambassador to Washington Husain Haqqani acknowledged there were "cracks through which things fell through" and vowed Pakistan would investigate, but insisted officials were unaware that bin Laden was hiding so close.
"If any member of the Pakistani government, the Pakistani military or the Pakistani intelligence service knew where Osama bin Laden was, we would have taken action," he continued.
Donilon said a "good starting point" for Islamabad would be to provide direct access to bin Laden's detained widows.
"They have in their custody all the non-combatants from the compound, including three wives of Osama bin Laden," he said.
Washington had yet to be given access, Donilon said, but "we haven't been told we can't either at this point. We'll certainly press on this very hard."
Pakistani security officials say bin Laden's Yemeni wife, who was shot in the leg during the raid, is undergoing medical treatment and interrogation in Pakistan along with 15 other relatives, many of them children.
"She said in Arabic that bin Laden and his family were living in this compound for the last five years and he never left the compound," one official said, speaking on condition of anonymity.
As the diplomatic fallout from bin Laden's killing intensified, the White House, meanwhile, rowed back on previously announced plans for Obama to visit Pakistan this year, saying no such trip was scheduled at this time.
For a decade, Islamabad has been America's wary Afghan war ally, despite widespread public opposition and militant bomb attacks across the nuclear-armed country that have killed several thousand people.
But Pakistan has never been fully trusted by either Kabul or Washington, which accuse its powerful military of fostering the Afghan Taliban it spawned during the 1980s resistance to the Soviet occupation of Afghanistan.
NATO chief Anders Fogh Rasmussen said western powers will nonetheless "stay the course" in Afghanistan, despite bin Laden's death and growing calls for the decade-old war to end.
"International terrorism still poses a threat toward our countries," Rasmussen told Fox News.