Bangui - After seizing Birao and Ouadda Djalle in the far north of the Central African Republic, the rebel Union of Democratic Forces for the Rally advanced towards the west on Sunday, threatening the mining town of Bria.

"Since Birao then Ouadda Djalle were taken, the rebels have been moving towards the west in the direction of Bria, nearly 600km north-east of the capital Bangui," a CAR government official told AFP on condition of anonymity.

The official said the rebels had already taken control of Sam Ouandja, a small town between Ouadda Djale and Bria.

"We are currently moving towards Bria and Ndele," 250km north-west of Bria, near the Chad border, Captain Yao, a leading rebel, told AFP by telephone. "If the leaders give us the order, we will attack," he added.

"We are not meeting any resistance from the Central African armed forces," he said. "There has been no fighting since Friday and the taking of Ouadda Djalle and many soldiers from the government's army joined us," he added.

A military source interviewed by AFP confirmed the rebel troop movements towards Bria.

Witnesses contacted by AFP reported seeing the rebels. "These men wearing civilian clothes and military uniforms talk Arabic or Sango (CAR's official language). They are advancing in groups using rural paths to avoid the main roads," one local north of Bria said.

The CAR is one of Africa's poorest countries and government control of the unstable north is tenuous at best. - Sapa-AFP