The African Union says at least 10 of its soldiers have been killed in an attack on an AU peacekeeping base in Sudan's Darfur region.
An African Union statement Sunday said 50 other people are missing following a sustained assault on the Haskanita base in southern Darfur late Saturday.
An AU spokesman, Nourreddine Mezni, says the killings represent the AU's "heaviest loss of life" in Darfur since the peacekeepers were deployed in 2004. He said seven other soldiers were wounded in the attack.
No group has claimed responsibility for the attack, but AU military officers are blaming Darfur rebels.
Rebel commanders acknowledge their forces have been fighting Sudanese government troops near Haskanita in recent days.
AU. officials condemned the attack, calling it a violation of a ceasefire agreement signed last year.
That ceasefire, signed by one faction of the rebel Sudan Liberation Army, has had little effect on stopping the violence in Darfur.
The western Sudanese region has endured more than four years of fighting between rebel groups, militias, and the Sudanese government. The violence has killed an estimated 200,000 people and driven more than two million others from their homes.
The overwhelmed AU peacekeeping force of 7,000 is due to be strengthened next year by the arrival of 19,000 more troops and police operating under joint U.N. and AU oversight.
Meanwhile, a group of so-called elders led by South African Archbishop Desmond Tutu is due to arrive in Sudan Sunday with the goal of assisting Darfur peace efforts. The group includes former U.S. President Jimmy Carter and former U.N. envoy Lakhdar Brahimi.
Peace talks between the various rebel groups and the Sudanese government are scheduled to begin in Tripoli, Libya on October 27.
Some information for this report was provided by AFP, AP and Reuters.