Casualties continued to climb Thursday in Libya due to both clashes between pro- and anti-government forces, and strikes by NATO-led military warplanes.

Four people died and 10 others were wounded in a fight between forces loyal to Libyan leader Muammar Gaddafi and rebels in eastern oil town of Brega, a medical source from a hospital in the town of Ajdabiyah, some 60-70 km from Brega, told Xinhua Thursday.

Xinhua reporters saw hospital workers and rebel fighters, carrying the bodies, patrol the hospital yard and shout "all those who had protected our lives are martyrs."

The bodies were afterwards carried away by a car. A doctor sobbed he felt sad he failed to save the lives of the fighters, while Xinhua reporters saw NATO fighters overhead.

Meanwhile on Thursday, anti-government fighters said government forces had retaken Brega and were heading towards Ajdabiyah where residents were fleeing. The rebels had said Wednesday that government forces withdrew from Brega after fierce overnight clashes.

Government troops and the opposition fighters have traded fire in Brega and Ras Lanuf in the past two weeks after the United Nations passed a resolution imposing a no-fly zone over Libya.

Also Thursday, at least two rebels were killed by a NATO airstrike near Brega, while about 10 others were injured, sources with the rebels said, adding that several of their tanks were destroyed.

The rebels were further enraged by the "accidental" consequences of NATO's non-selective strikes, with the latest deaths coming less than a week after a West-led air raid last Saturday left 13 rebel fighters dead.

While NATO is yet to confirm the latest rebel deaths, it was busy dismissing on Thursday the Libyan government's accusation that Britain had bombed the country's biggest oil field the previous day.

Libyan Deputy Foreign Minister Khaled Kaim on Wednesday blamed Britain for attacks on the Sarir oil field, which reportedly killed three guards and a number of oil workers, and left many more wounded.

Lieutenant General Charles Bouchard, commander of the NATO mission, said in a statement Thursday the accusation was false, as NATO had never carried out strike operations in the oil field.

Bouchard said the fire "is a direct result of his (Gaddafi's) attacks on his own people and infrastructure."

He said NATO knew Gaddafi wanted to disrupt oil getting to Tobruk, an eastern town currently controlled by the rebels.

VietNamNet/Xinhuanet