The kidnapping of Libyan Prime Minister Ali Zeidan by gunmen from a Tripoli hotel appears to be retaliation for the capture by American forces of a wanted al-Qaeda-linked operative.
He was photographed being led away from the Corinthia Hotel on the city's sea-front in the early hours of the morning local time.
Officials said he seemed not to have been harmed, and added to confusion over the reasons for his being taken away by saying that two "revolutionary brigades"were believed to be responsible - the "Operations Room of Revolutionaries" and the "Brigade for the Fight against Crime".
Both theoretically are under government control, and told local reporters he had been arrested for alleged bribery on orders from the justice minister and the chief prosecutor, a claim they denied.
One said he faced charges of corruption and breaching state security, though the other also referred to a statement by John Kerry, the US Secretary of State, that the Libyan authorities had been aware in advance of the US capture last weekend of Abu Anas al-Libi, who is wanted for trial in New York.
Staff at the hotel, where he had been living because of previous threats, said the militias had arrived to "arrest" Zeidan. A photograph apparently provided by the militias themselves and posted on the Al-Arabiya website showed a confused Zeidan, without his trademark spectacles, in what appeared to be night-clothes.
"The head of the transitional government, Ali Zeidan, was taken to an unknown destination for unknown reasons," a government statement posted on the Prime Minister's Facebook site said. Officials said an earlier statement denying the kidnapping had been posted at the same place on the kidnappers' instructions.
There was an angry reaction in Libya and particularly among Islamist militias to the capture on Sunday by US Delta Force Marines of al-Libi, a founder member of the Libyan Islamic Fighting Group, an opposition organisation in the time of Colonel Muammar Gaddafi.
Al-Libi, whose real name is Nazih Abdulhamad al-Ruqai, was indicted in a New York court in 2001 on charges of helping to plan the al-Qaeda bombings of the US embassies in Nairobi and Dar el-Salaam which killed 224 people. After a career which had seen him moved between Sudan, Britain, Afghanistan and Iran, he had returned to live openly with his family in Tripoli after the 2011 revolution began.
At the time of the raid, Zeidan said he had not been informed in advance and demanded "clarification"to the US authorities. But US officials briefed reporters in Washington that the Libyan authorities had been given general notification though not the precise details of the raid. Al-Libi's family said that men speaking the Libyan dialect of Arabic were involved, leading many to believe that the Government was involved. In any case, Zeidan came under fire for failing to stand up for Libyan sovereignty.