The brazen abduction, which ended with Zidan's rescue, underscored the lawlessness gripping Libya two years after the ouster of autocrat Moammar Gadhafi. The weak central government is virtually hostage to multiple, independent-minded militias - many of them made up of Islamic militants - that serve as security forces and hold sway across the country.
The gunmen who abducted Zidan were believed to be militiamen, and it appeared he was freed when members of another militia stormed the site where he was being held.
Thursday afternoon, after authorities announced he had been freed, Zidan spoke at a Cabinet meeting aired live on Libyan TV. He thanked those who helped free him but provided no details and avoided pointing fingers at those behind the abduction.
"We hope this matter will be treated with wisdom and rationality, far from tension," he said. "There are many things that need dealing with."
The incident raised alarm over the power that militias hold over government officials. The militias originated in the informal brigades of "revolutionaries" who fought Gadhafi's forces in the 2011 revolt against his rule. Since Gahdafi's ouster and death, the groups have resisted efforts to disarm them, multiplied in number and mushroomed in size.
With the regular police forces and army weak and in disarray, the government has had to enlist some militias to act as security forces. But they often remain more loyal to their own agendas and commanders than the state, and many have hard-line Islamic ideologies sympathetic to al-Qaida. They frequently lash out at officials to get their way. Last month, the son of the defense minister was abducted, and there are frequent killings of security officials who cross militiamen.
"The abduction is like the shock that awakened Libyans. Facts on the ground now are clearer than never before: Libya is ruled by militias," said prominent rights campaigner Hassan al-Amin.
The motive for Zidan's abduction was not immediately known. But it comes after many Islamic miltiants and militas expressed outrage over the U.S. raid on Saturday that seized al-Qaida suspect Nazih Abdul-Hamed al-Ruqai, known by his alias Abu Anas al-Libi. They accused Zidan's government of colluding in the operation and allowing foreigners to snatch a Libyan from Libyan soil. The government said it had no knowledge of the raid.
Before daylight Thursday, around 150 gunmen in pickup trucks laid siege to downtown Tripoli's luxury Corinthia Hotel, where Zidan resides, witnesses told The Associated Press. A large group of them entered the building, some stayed in the lobby while others headed to Zidan's residence on the 21st floor.
The gunmen scuffled with the prime minister's guards before they seized him and led him out at around 5.15 a.m., said the witnesses, speaking on condition of anonymity because they feared for their own safety. They said Zidan offered no resistance while he was being led away.
The circumstances of his freeing were unclear. In the afternoon, government spokesman Mohammed Kaabar told the LANA new agency that Zidan had been "set free." The brief report gave no further information.
But it appeared Libyan forces had intervened in some way and that the abductors did not free Zidan voluntarily.
A militia commander affiliated with the Interior Ministry told a private Libyan television station that members of a Tripoli-based militia stormed the house where Zidan was held hostage and rescued him.
Haitham al-Tajouri, commander of the so-called "Reinforcement Force," told Al-Ahrar television that his men exchanged fire with the captors but that Zidan was not hurt.
"He is now safe in a safe place," he said. His account could not be independently verified.
Suspicion of who is behind the kidnaping fell on two state-affiliated agencies connected to militias - "the Revolutionaries Operation Room" and "the Anti-Crime Department, which have been set up by Nouri Boushameen, president of the National Congress, or parliament.
Boushameen later sought to distance himself from the kidnapping, telling a news conference that members of the two agencies who took part in the abduction would be punished.
He said he visited the prime minister while in captivity and promised to resolve the crisis.
U.S. Secretary of State John Kerry said at a news conference in Kuala Lumpur, Malaysia, "It is clearly a situation that is still evolving. The Libyan prime minister to our understanding has been released. It our understanding that there has been no statement issued yet as to the who, what, why and how."
Zidan's abduction came hours after he met Wednesday evening with al-Libi's family. Al-Libi is alleged to be a senior al-Qaida member and is wanted by the United States in connection to the bombing of American embassies in Tanzania and Kenya in 1998, with a $5 million bounty on his head. U.S. officials say he is now being held on an U.S. warship.
On Tuesday, Zidan said the Libyan government had requested that Washington allow al-Libi's family to establish contact with him. Zidan insisted that Libyan citizens should be tried in their homeland if they are accused of crimes, stressing that "Libya does not surrender its sons."
Still, he said relations with Washington, a key ally of his government, would not be effected.
Immediately after the raid, the Libyan government issued a statement saying it was carried out without its knowledge and asking Washington for "clarifications" about the operation.
In Brunei, U.N. Secretary-General Bank Ki-moon condemned the abduction and called it a "clear wake-up call" for countries undergoing democratic transitions.
"It would be very important for the Libyan government and its leadership to ensure inclusive dialogue and rehabilitation so that all the people can join the process," Ban said during an Asian summit.
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