The African Union (AU) on Tuesday expressed regret over the killing of two civilians in Western Darfur on Sunday. The AU says African mission troops were forced to fire on rioters who attacked their base in Western Darfur. For VOA, Noel King has this report from Khartoum.

The African Union says its base in the Western Darfur city of El Geniena was stormed by the relatives of civilians who were killed in an attack on a relief convoy late last week. Armed men on horseback shot and burned to death 30 civilians during Saturday's attack near Sirba village, spurring an angry response from village residents.

The AU says it acted in self-defense when peacekeepers fired on armed civilians who were protesting the AU's inability to prevent violence in the region.

AU spokesman Noureddine Mezni expressed regret about the incident from Khartoum but said the response was justified.

"It is the first time our troops found themselves is such a situation. Among the civilians who were demonstrating there were some armed people. They used force to enter into the camp," he said. "It is regrettable but they had to do it because there was no other means. Otherwise they could have been killed."

Mezni called for those in the region to remain calm, stressing that the AU is in Darfur to protect civilians.

But Sunday's incident again cast doubt on the capability of the AU force to stem a rising tide of violence in the region.

The cash-strapped AU mission has only about 7,000 peacekeepers patrolling a remote area the size of France.

Sporadic but violent clashes erupt frequently throughout Darfur and AU observers often arrive on the scene after attacks. Critics have called for U.N. intervention in the region, but Sudan's government has staunchly denied U.N. entry.

The AU has voted to extend its mandate until June 2007 to prevent a security vacuum in Darfur.

On Tuesday Commander Jar El Naby, of Darfur's Sudan Liberation Army told VOA that eight civilians, including a mother and her five children were killed in a government air strike on a village in north Darfur on Monday.

A spokesman for the Sudan Armed Forces denied the charges.

The Darfur conflict, soon to enter into its fourth year, began when rebels attacked government positions complaining that the region remained undeveloped due to neglect by the central government.

Sudan is charged with arming militias known as Janjaweed to crush the rebellion using a savage campaign of rape and murder - charges it denies.