BENGHAZI, Libya - Moammar Gadhafi's forces swept rebels from a key oil town Sunday with waves of strikes from warships, tanks and warplanes, closing on the opposition-held eastern half of Libya as insurgents pleaded for a U.N.-imposed no-fly zone.

Gadhafi's troops have been emboldened by a string of victories in the struggle for Libya's main coastal highway but their supply lines are stretched and their dependence on artillery, airstrikes and naval attacks makes it hard for them to swiftly consolidate control of territory, particularly at night.

The insurgents claimed they moved back into the strategic town of Brega after dusk in a fast-moving battle with a constantly shifting front line, destroying armored vehicles and capturing dozens of fighters from Gadhafi's elite Khamis Brigade.

The United States sent U.S. Secretary of State Hilary Rodham Clinton to meet with rebel leaders in Paris on Monday as world powers consider trying to ground Gadhafi's air force.

The Obama administration and other governments have expressed deep reservations about a tactic that would require them to destroy Gadhafi's air defenses and possibly shoot down his planes. The Arab League raised the pressure on the U.S. and its NATO allies on Saturday by asking the U.N. Security Council to impose a no-fly zone, but a day later they appeared no closer to taking action.

"This was a rare decision of the Arab League," rebel spokesman Abdul Basit al-Muzayrik told Al-Jazeera. "We call on the international community to quickly make a firm decision against these crimes."

The poorly equipped and loosely organized rebel fighters said throughout the day they were fleeing the oil town of Brega under heavy attack, losing a vital source of fuel for their vehicles and leaving Gadhafi's military less than 150 miles from the main opposition city of Benghazi.

A spokesman for Gadhafi's military declared it had seized control of the town and was "dealing with the situation."

It was impossible to independently confirm either side's account because it has become too dangerous for reporters to operate in the contested area.

Ajdabiya is the only other major population center between Gadhafi's forces and the rebel headquarters.

If his successes continue, the Libyan strongman will soon face the choice of consolidating his control of the Mediterranean coast or moving swiftly toward Benghazi and the prospect of a devastating battle.

"Benghazi doesn't deserve a full-scale military action," army spokesman Milad Hussein told reporters in the capital, Tripoli. "They are a group of rats and vermin and as soon as we go in, they will raise their hands and surrender."

Gadhafi's navy, army and air force began pounding Brega with artillery, rockets and bombs Sunday morning and didn't let up all day, forcing doctors and wounded people from the town's hospital with a missile strike, several rebels told The Associated Press after fleeing.

"There wasn't any time to breathe, to do anything," one fighter with responsibility for logistics said by telephone as he fled Brega for Ajdabiya, about 50 miles (80 kilometers) by road to the east. Explosions went off in the background.