Al-Libbi, a Libyan who authorities say is a close associate of Osama bin Laden and acted as al Qaeda's operational chief in Pakistan, was arrested earlier this week, Information Minister Sheikh Rashid Ahmed told The Associated Press.
"This is a very important day for us," Ahmed said.
Interior Minister Aftab Khan Sherpao said al-Libbi was an "al Qaeda planner" with a senior place in the terror group's hierarchy. He said the U.S. government was offering a $10 million bounty for information leading to the man's arrest, though he does not appear to be on the FBI list of most wanted terrorists.
Neither minister would say where al-Libbi was captured or being held.
But three Pakistani intelligence officials told AP on condition of anonymity that al-Libbi was one of two foreigners arrested Monday after a firefight on the outskirts of Mardan, 30 miles north of Peshawar, capital of the conservative North West Frontier Province.
One of the officials said 11 more terror suspects — three Uzbeks, an Afghan and seven Pakistanis — were arrested Wednesday in the Bajor tribal region. The official would not say whether the arrests were linked to al-Libbi's capture.
The intelligence officials said authorities were led to al-Libbi's hide-out by a tip-off that foreigners had been spotted nearby. Al-Libbi was held overnight at a Mardan military facility, then taken by helicopter to the capital, Islamabad, the officials said.
In a speech on Social Security, President Bush said the arrest "represents a critical victory in the war on terror," reports CBS News Chief White House Correspondent John Roberts.
A U.S. intelligence official calls al-Libbi the terror network's number-three leader, after bin Laden and his top deputy Ayman al-Zawahri.
Bush also praised Pakistan for what he called "strong cooperation" in the war on terror -- and for acting on "solid intelligence" supplied by the United States.
Sherpao would not speculate on whether the arrest might help lead to the capture of bin Laden or his deputy, Ayman al-Zawahri, who have eluded a 3 1/2 year dragnet since the Sept. 11, 2001 attacks.
"We have no information" about the al Qaeda leaders, he said. "It's premature to say (whether al-Libbi's arrest will help find them), but definitely interrogation is going to take place,"
When asked whether Pakistan was close to capturing bin Laden, Ahmed said "this arrest gives us a lot of tips, and I can only say that our security agencies are on the right track."
He said Pakistani security agents have already gleaned much information from the arrest.