The suspected Sept. 11 mastermind was not the only big catch in recent weeks by American and Pakistani authorities: U.S. officials say another senior Al Qaeda operative and a suspected financier of the attacks on the World Trade Center and the Pentagon also have been taken into custody.

The alleged senior operative, Mohammed Omar Abdel-Rahman, is a son of the blind Egyptian sheik accused of inspiring the 1993 bombing of the World Trade Center.

The younger Abdel-Rahman was caught several weeks ago in Quetta, Pakistan, the officials said, speaking on condition of anonymity. Pakistani officials have suggested the Quetta arrest helped lead authorities to Khalid Shaikh Mohammed, although American sources disputed that, saying Mohammed was found by other, unspecified means.

Government officials said Abdel-Rahman ran a training camp in Afghanistan before the Sept. 11 attacks and also had a role in operational planning. He is considered a senior Al Qaeda operative, one of several operations chiefs who rank one tier below Mohammed in the Al Qaeda hierarchy.

He is known as Asadullah, "the Lion of God." His father, Omar Abdel-Rahman, is in a U.S. prison for a 1994 plot to bomb landmarks around New York City.

Another son of the blind sheik, Ahmad, was captured in Afghanistan in late 2001.

Officials also identified a man captured with Mohammed on Saturday as suspected financier of the Sept. 11 attacks. His name and nationality were unclear. Pakistani Ahmed Abdul Qadus was also detained with the two.

At least two Al Qaeda operatives with direct financial ties to the hijackers remain at large, Mustafa Ahmed al-Hisawi and Ali Abdul Aziz Ali. Little is known about either.

Mohammed was questioned Monday by U.S. authorities seeking information about safe houses and hideouts used by the Al Qaeda terror network, a Pakistani intelligence official said. Mohammed's exact whereabouts were unclear.

He had been plotting attacks against targets in the United States and Saudi Arabia in the weeks before his capture, U.S. counterterrorism officials contended.

Such attacks might have been against commercial or other lightly defended civilian targets, officials said, although they acknowledged they did not know whether specific sites had been selected.

Intelligence about Mohammed's activities led in part to the nationwide orange alert that lasted most of February, Homeland Security Secretary Tom Ridge said.

"Some of the concerns we had that caused us to raise the threat level were attributable to the planning he was involved in," Ridge said. "There were multiple reasons that we raised the threat level and his relation to one of the plot lines was one of the several."

Ridge declined to discuss specifics but said the threat level was lowered last week because later information showed that plans for attacks had been disrupted and were less likely to occur.

Authorities recovered a huge amount of information about Al Qaeda at the house in Pakistan where Mohammed and two others were arrested early Saturday, a senior law enforcement official said Monday.

Found at the home in Rawalpindi were computers, disks, cell phones and documents. Authorities believe the materials will provide names, locations and potential terrorist plots of Al Qaeda cells in the United States and around the world.

Mohammed also was believed by U.S. officials to have details about the group's finances.

White House spokesman Ari Fleischer said, "We are hoping that this will lead to substantial additional information on Al Qaeda, on Al Qaeda's plans and Al Qaeda's operations."

Officials expressed concern that Al Qaeda cells could accelerate plots in the United States and elsewhere rather than run the risk of being captured. Or cell members might also go into hiding, believing their security was compromised by Mohammed's capture.

Mohammed is suspected of trying to send deputies into the United States at least twice since Sept. 11, officials said.

Mohammed, in his late 30s, is perhaps the most senior Al Qaeda member after bin Laden and his deputy, Ayman al-Zawahri.

He is alleged to have organized the Sept. 11, 2001, terror attacks that killed some 3,000 people in New York, at the Pentagon and in Pennsylvania, and was linked to a 1995 plot to bomb trans-Pacific airliners and crash a plane into CIA headquarters and to the 1993 World Trade Center bombing.

He also has been tied to the April bombing of a synagogue in Tunisia, which killed 19 people, mostly German tourists.