TRIPOLI, Libya - Two former Libyan rebel factions clashed on Tuesday in hours of gunbattles in central Tripoli that left five fighters dead, a Tripoli military council official said.

Former rebels of Tripoli and a separate group of fighters from the city of Misrata fought with machine guns, rocket-propelled grenades and anti-aircraft guns. Col. Walid Shouaib, a member of Tripoli Military Council, said the clashes were triggered by arrest of a Misrata fighter on New Year’s Eve by Tripoli fighters. He was suspected of robbery and the Misrata fighters were trying to free him.

A Misrata military council member, Mohammed al-Gressa, said he feared a civil war. He said a meeting was taking place between commanders of ex-rebels and the Tripoli military council.

“I am not optimistic because blood has been spilled,” he told The Associated Press. “I feel this looks like a civil war.”

Others said the clashes were not that serious.

Disparate groups of former revolutionary fighters have clashed repeatedly since the end of the eight-month civil war that toppled Moammar Gaddafi’s regime in October. Disbandment of these armed groups, which are divided by the regions where the operate, has posed a challenge to Libyan authorities.

While playing a vital role in overseeing security of key state institutions in the capital, the uncontrolled ownership of weapons and the absence of a central security administration has given the militias a free hand in ruling areas under their control.

According to Shouaib, the tensions between the two militias began on the night of the arrest when a group of Misrata fighters tried to free the detained man, but failed. Instead, they were arrested as well. A top Misrata commander managed to mediate the release of all the men except for the one arrested for robbery.

On Tuesday, another group of Misrata fighters made a second attempt to free the man. They opened fire on a building in the heart of Tripoli and used by the Tripoli military council. After hours of gunbattles, three of Misrata fighters and two from Tripoli armed men were killed, Shouaib said.

Witnesses said the Tripoli militia arrested six Misrata men, brought them inside the council building, beat them up and detained them. The Tripoli council is affiliated with the national transitional government.

Government spokesman Ashur Shamis played down the scale and severity of the armed confrontation and defended revolutionaries as “innocent.” Instead, he blamed clashes on “saboteurs.”

“These skirmishes take place because of individual animosities but have nothing to do with the revolution or the revolutionaries,” Shamis said. “The real and original revolutionaries are not part of it.”

He insisted that the Interior Ministry is in control of the situation.

Ibrahim Beit al-Mal, a spokesman for Misrata fighters, agreed. “These incidents are driven by misguided youth,” he said. “These are not the revolutionaries.”

He added, “Our slogan is: Libya is united, and its capital is Tripoli.”