A US interrogation team is questioning the alleged senior al-Qaeda figure who was seized by special operations forces in Libya and then whisked onto a navy ship in the Mediterranean Sea, US officials said.
Nazih al-Ragye, better known by the cover name Abu Anas al-Liby, is being held aboard the USS San Antonio, an amphibious transport dock ship, the officials said on Monday.
He is being questioned by the US High Value Detainee Interrogation Group, an inter-agency unit created in 2009 and housed in the FBI's National Security Branch.
The group specialises in garnering information from suspects to prevent planned attacks.
A suspect in the 1998 bombings of the US embassies in Kenya and Tanzania that killed 224 civilians, Liby was captured on the streets of Tripoli on Saturday and quickly taken out of the North African country.
The successful capture of Liby and a failed weekend attempt by US commandos to capture an al-Shabab leader in Somalia offered evidence that the US is still willing to use ground troops to seize wanted figures.
Call for revenge
The raid in Tripoli was carried out by the US army's special operations Delta Force, an official said.
Libyan armed groups called for the kidnapping of American citizens in Tripoli and for attacks on gas pipelines, ships and planes to avenge the capture of Liby.
Messages posted by Libyan fighters on the internet and monitored by the SITE service included a Facebook page called "Benghazi is Protected by its People".
It told Libyans to close off entrances and exits to the capital and kidnap citizens of the United States and its allies
in order to use them to bargain for the release of imprisoned fighters.
It also urged them to damage pipelines exporting gas to Europe, and target ships and planes.
"Libya today is still a place of disbelief that is ruled by something other than the Shariah of Allah; thus, there is no
security for disbelievers there," the message said.
In another message posted on forums and social media, a group called "the Revolutionaries of Benghazi - al-Bayda, Derna" condemned the al-Qaeda leader's capture.
Liby's wife, Uma Abderahman, told Al Jazeera that her husband was taken from his home by masked men.
"There was at least ten of them and they were all armed, with silenced weapons," she said. "It seems like they had drugged him."
He is clearly al-Qaeda and he is clearly wanted on charges... When we are able to, we prefer to capture someone like Mr al-Liby.
Liby is wanted by the FBI, which gives his age as 49 and had offered a $5m reward for help in capturing him.
He was indicted in 2000 along with 20 other al-Qaeda suspects including Osama bin Laden and current global leader of the network, Ayman al-Zawahri.
Liby's indictment was filed in New York, making that a possible venue for a civilian, rather than military, trial.
One US official said he might face prosecution in New York, but the US government has not announced its plans and no decision has been made.
Liby's capture provoked a complaint about the "kidnap" from the Western-backed Libyan prime minister. US officials declined to say if the Libyan government was given advance notice.
On Tuesday, Libya's government summoned US ambassador Deborah Jones to seek clarification over the capture of Liby.
"Justice Minister Salah al-Marghani summoned the ambassador of the United States on Monday morning to ask for answers to several questions relating to the case" of Abu Anas al-Libi, a ministry statement said.
The White House defended the US action. It marked the use of "rendition" - seizing a suspect in a foreign country without extradition proceedings, a practice heavily criticised internationally under former President George W Bush but which President Barack Obama has reserved the right to use selectively.
"He is clearly al-Qaeda and he is clearly wanted on charges," White House spokesman Jay Carney told reporters of Liby's case.
The capture in Tripoli came the same weekend that a navy SEAL team swooped into Somalia in an operation targeting a senior al-Shabab figure known as Ikrima, whom US officials described as a foreign commander for the organisation.
Obama, who ordered the SEAL raid that killed bin Laden in 2011, approved both operations but they were planned separately.
"It is a coincidence that they happened at the same time," Carney said.