A fierce gunfight between two tribes in Libya's remote southeastern desert has killed six people in the past two days and wounded another 20, officials and tribal sources told AFP on Monday.

Clashes between members of the Zwai and Tobu tribes in the town of Kufra killed five people on Sunday, while one person was slain in a firefight on Monday, tribal sources said.

Mohammed al-Harizi, spokesman of Libya's ruling National Transitional Council, confirmed Sunday's clashes, saying 20 people were wounded in addition to the five dead.

"It was a problem between two tribes and they are working to find a peaceful solution," he told AFP, without naming the tribes.

A member of the Zwai tribe told AFP that new clashes on Monday had killed one of their comrades.

Both groups were using light arms when the fighting initially erupted, but the violence then intensified, with the two sides firing rocket-propelled grenades and anti-aircraft guns, sources said.

A militant from Tobu tribe said those fighting him and his comrades since Sunday were Zwai tribesmen supported by the NTC.

"There is a plan to exterminate the Tobu tribe. Our situation is worse than what it was under Kadhafi," he said without giving his name.

Of the five killed on Sunday, he said two were from the Tobu tribe, whose members are dark-skinned and were discriminated against even under the regime of slain dictator Moamer Kadhafi.

The latest clashes apparently erupted after a young man from the Zwai tribe was killed in Kufra by three dark-skinned men believed to be from the Tobu tribe three days ago, a source from the Zwai tribe said.

The desert town also witnessed deadly clashes during last year's anti-Kadhafi uprising, which erupted across the country and ended with the strongman's death in October.