A high-ranking Al Qaeda leader suspected of masterminding the Sept. 11 terror attacks is being held at the main U.S. military base in Afghanistan after his weekend capture, a Pakistani official said Tuesday.

However, a U.S. military spokesman at Bagram Air Base refused to confirm the whereabouts of Khalid Shaikh Mohammed.

Pakistan Information Minister Sheikh Rashid Ahmed said Mohammed was handed over Tuesday to U.S. authorities, who took the alleged No. 3 man in Al Qaeda to their interrogation center at Bagram Air Base.

Mohammed was arrested Saturday in a joint raid by CIA agents and Pakistani police in Rawalpindi, Pakistan. His capture was a big victory in the U.S. hunt for terror suspects.

Since then, Mohammed's location has been the subject of conflicting reports.

Some say he was taken directly to Bagram after his capture, joining an unknown number of Al Qaeda and Taliban suspects at a secret holding facility.

Others say he spent a few days in Pakistan, where he was questioned by Pakistani authorities.

Col. Roger King, the spokesman for U.S. and coalition forces in Afghanistan, refused to comment Tuesday on the Pakistani Cabinet official's claim.

"As far as anyone being taken under coalition control, anybody coming through Bagram, anybody going to other places, we don't comment on it," King told The Associated Press.

King refused to speculate on whether Mohammed could provide useful information for tracking down Al Qaeda leader Usama bin Laden.

But, he said, "We find that virtually everybody gives you something that's useful. Whether it would go toward that specific end [finding bin Laden], I really wouldn't want to go down that road because it's really early in the game."

U.S. military officials routinely refuse to comment on the identities or nationalities of detainees -- even low-level detainees -- at Bagram, where prisoners are kept under tight security in a two-story tan building surrounded by a gray wall and barbed wire.

King said U.S. military police in the compound were guarding "up to 100" detainees, the majority of whom were captured during coalition operations inside Afghanistan. Another large detention center in the southern city of Kandahar was shut down last year.

The center is viewed as a "temporary facility," King said, though he declined to comment about how long a suspect like Mohammed could be held there.

As a general rule with a detainee, "It depends on what we think the individual might know, what we think the individual may have done. It's all dependent upon the individual and who that person is," King said.

Methods of interrogation at the base have been criticized by human rights groups such as Amnesty International, especially after the Washington Post reported last year that the methods allegedly included forcing inmates to stand or kneel for hours while wearing black hoods or spray-painted goggles, holding them in "awkward, painful positions" and depriving them of medical care or sleep with a "24-hour bombardment of lights."

The military flatly denies the report, saying the prisoners are all treated humanely and allowed to meet regularly with representatives of the International Red Cross. The United States maintains it strictly adheres to international law prohibiting torture, but officials say they can use psychological inducements to get suspects to talk.

ICRC spokesman Simon Schorno said delegates "very regularly" visit the Bagram detainees, but he declined to detail their conditions.

King said two prisoners died at the Bagram facility in December and those deaths were being investigated by the U.S. military.