BENGHAZI, Libya -- Eight British special forces personnel who had been detained by rebel forces have left Libya aboard the HMS Cumberland, Sky News reports.

The capture of as many as eight British soldiers by Libyan rebel forces had prompted a "small British diplomatic team" to start talks with the anti-government troops, U.K. Defense Secretary Liam Fox confirmed.

The eight Special Air Service soldiers were captured after a secret mission to put British diplomats in touch with opponents of Libyan leader Muammar al-Qaddafi, according to the London Times. The soldiers were captured Saturday as they escorted a junior diplomat through rebel-held territory in eastern Libya, according to the paper.

"The team went to Libya to initiate contacts with the opposition," Foreign Secretary William Hague told Sky News. "They experienced difficulties which have now been satisfactorily resolved."

Anti-government forces created the 30-member council in the eastern city of Benghazi after the liberation of several eastern cities, reported AFP. Led by former justice minister Mustafa Abdel Jalil, the council reportedly plans to lead the country toward a national election.

The detainment came as Libyan warplanes launched airstrikes and forces loyal to Qaddafi engaged in fierce ground battles Sunday with a rebel force advancing west toward the capital Tripoli along the country's Mediterranean coastline.

The opposition fighters pushed out of the rebel-held eastern half of Libya late last week and have been cutting a path west toward Tripoli. On the way, they secured control of two important oil ports at Brega and Ras Lanouf. By Sunday, the rebels were advancing farther west when they were hit by airstrikes and resistance from ground forces.

Associated Press reporters at the scene said Qaddafi loyalists retook the town of Bin Jawad, about 110 miles east of Qaddafi's stronghold city of Sirte, which could prove to be a decisive battleground. The reporters witnessed airstrikes on the rebel forces and heavy fighting on the ground.

The uprising that began on Feb. 15, inspired by rebellions in neighboring Tunisia and Egypt, has been sliding toward a civil war that could be prolonged, with rebels backed by mutinous army units and arms seized from storehouses going on the offensive to try to topple Qaddafi's 41-year-old regime. At the same time, pro-Qaddafi forces have tried to conduct counteroffensives at Brega and in the rebel-held city of Zawiya west of Tripoli -- where bloody street battles were reported over the weekend.

The U.S. has moved military forces closer to Libya's shores, but has expressed wariness about talk of imposing a "no-fly zone" over the North African nation to prevent Qaddafi from using his warplanes to attack the population. The U.N. has imposed sanctions, and Libya's oil production has been seriously crippled by the unrest. The turmoil has caused oil prices to spike on international markets.

In Tripoli, the city of 2 million that is most firmly in Qaddafi's grip, residents were awoken before dawn by the crackle of unusually heavy and sustained gunfire that lasted for at least two hours.

The reason for the gunfire was not immediately clear, though Libyan authorities said it was to celebrate the regime taking back Ras Lanouf near the rebel-held east and the city of Misrata close to Tripoli. Despite those claims, AP reporters saw the rebels in control of Ras Lanouf early Sunday and residents of Misrata said the city remained in opposition hands.

By early morning, thousands of Qaddafi's supporters poured into Tripoli's central square for a rally, waving green flags, firing guns in the air, and holding up banners in support of the regime.

Hundreds drove past the Bab al-Aziziya military camp where Qaddafi lives, waving flags and cheering. Armed men in plainclothes were standing at the gates, also shooting in the air. Qaddafi's whereabouts were unknown.

The Associated Press contributed to this report