Updated

Pakistan will turn over the Taliban's former ambassador to that country and the Al Qaeda leader who ran terrorist training camps in Afghanistan, according to U.S. officials.

Former ambassador Mullah Abdul Salam Zaeef has been taken to the detention facility built by marines in southern Afghan city of Kandahar for questioning.

A U.S. official says Zaeef potentially has a considerable amount of useful information. Pakistani officials have already questioned Zaeef in the city of Peshawar. 

In the Afghan capital, Minister of Planning Haji Mohammad Muhaqeq called Zaeef a criminal.

"I don't know of any particular crime, but Zaeef was a central figure, a member of the Taliban's inner circle and definitely committed crimes against humanity, in the world and in Afghanistan," Muhaqeq said.

The Al Qaeda leader, Ibn Al-Shaykh al-Libi, would be one of the highest-ranking members of the terrorist group to come under U.S. control. A second U.S. official, also speaking anonymously, said al-Libi is among Al Qaeda's "top 20" leaders.

While several of Usama bin Laden's chief lieutenants have been killed by U.S. bombs, al-Libi would be the most senior member of the group in U.S. custody.

The U.S. has already frozen al-Libi's assets, according to government documents.

Zaeef was being transported by "an army-backed intelligence agency," according to a senior Pakistani official who also wished to remain anonymous. The former ambassador would be one of the top two Taliban officials in U.S. custody, the other being Mullah Fazel Mazloom. Mazloom was captured by the Northern Alliance in November and turned over to the U.S.

Before the Taliban's fall, Zaeef spoke on their behalf from within Pakistan. After their fall, he applied for asylum in Pakistan.

Zaeef's nephew, Hamid Ullah, said Thursday that his uncle had been taken from his home in Islamabad.

"Since then we have not heard anything about him," Ullah said.

Pakistan had been the chief supporter of the Taliban until it agreed to cooperate with the U.S. military campaign. After Saudi Arabia and the United Arab Emirates cut their relations with the Taliban, Zaeef was the only Taliban envoy abroad.

The Associated Press contributed to this report.