Al Jazeera television has quoted Libyan rebels as saying they had regained control of the Libyan oil town of Brega.

Witnesses said Libyan leader Muammar Gaddafi's troops seized Brega.

Over the last weeks' fighting, both sides have frequently claimed victory in battles over towns long before any decisive action.

Rebel Colonel Hamed al-Hasi, introduced as rebel spokesman in Brega, told Al Jazeera: 'We have captured 20 of Gaddafi's forces and we killed 25. We have forced them to retreat 20 km from the town.'

Meanwhile, in Misrata residents said fighting broke out after some units of the Libyan army refused to attack Libya's third biggest city.

The reports of a mutiny could not be verified because Libyan authorities have not allowed reporters access to the city of 300,000 which is 200 km (130 miles) east of the capital.

Reports of a mutiny in Misrata, though unconfirmed, will raise questions about the ability of Gaddafi's security forces to press an offensive in the country's east, where the rebels have their biggest stronghold.

Residents had said the main force preparing to attack Misrata was the 32nd Brigade. This is commanded by Gaddafi's son Khamis and, according to military analysts, is the best trained and equipped force available to the Libyan leader.

Earlier, the US and Britain have welcomed the unanimous decision by the Arab League to ask the United Nations Security Council to enforce a 'no-fly zone' over Libya.

The 22 members of the League also decided to establish formal contacts with the rebels opposing Libyan leader, Colonel Gaddafi.

Meanwhile, Arab League Secretary General Amr Moussa said the League, meeting in Cairo yesterday, had decided that ‘serious crimes and great violation’ committed by the government of Muammar Gaddafi against his people had stripped it of legitimacy.

Washington, which would play a leading role in enforcing any no-fly zone, said the decision strengthened pressure on Gaddafi but it stopped short of commitment to military action and made no proposal for a swift meeting of the UN Security Council.

It took a week of repeated assaults by government troops, backed by tanks and air power, to crush the uprising in Zawiyah, a much smaller town 50kms west of Tripoli.

The death toll in Zawiyah was unknown but much of the town was destroyed, with buildings around the main square showing gaping holes blown by tank rounds and rockets.

Gaddafi's forces bulldozed a cemetery where rebel fighters had been buried.

Further east, Gaddafi's troops pushed insurgents out of Ras Lanuf, a day after making an amphibious assault on the oil port and pitting tanks and planes against rebels armed with light weapons and machineguns mounted on pick-up trucks.

Dozens of soldiers waved posters of Gaddafi and painted over rebel graffiti at a deserted housing complex for oil industry workers as foreign journalists arrived from Tripoli on a government-run visit to the recaptured city.