Chad's army killed 69 "Janjaweed" Arab militiamen in a clash near the border with Sudan's western Darfur region, a source close to President Idriss Deby said today.
Human rights groups have accused the Sudanese government of arming the Janjaweed to drive African villagers out of their homes in the Darfur region and have called the violence ethnic cleansing.
UN Secretary General Kofi Annan has warned of the risk of genocide in Darfur and said a military force may be needed in the region. He plans to visit Sudan soon to press Khartoum to do more to protect civilians and rein in the Janjaweed.
At least 120,000 Sudanese refugees are estimated to have fled to Chad to escape the fighting. The Chadian government and refugees have said the Janjaweed have made repeated incursions over the border.
The fighting in Darfur has driven more than a million people from their homes in what aid agencies and the UN have called one of the world's worst humanitarian disasters. Some two million in the region need outside aid, according to UN figures.