Gunmen killed five Rwandan soldiers in a series of attacks on the international peacekeeping force in Darfur, a spokesman for the mission said, marking a swift upsurge in violence in the western Sudanese region.
The attacks on Friday and Saturday targeted peacekeepers from the United Nations-African Union force, which deployed nearly two years ago to protect civilians and improve security in Darfur.
Fighting between rebels and Sudanese government forces began there in 2003, killing up to 300,000 people and driving 2.7 million from their homes. The government says those figures are exaggerated.
That violence has largely subsided, but the two attacks on peacekeepers demonstrate how vulnerable the under-funded and ill-equipped UNAMID force remains, as banditry and kidnappings of foreign aid workers continue to plague efforts to stabilize the vast desert region.
In Saturday's attack, assailants approached the gate of a camp for people displaced by the conflict and shot at peacekeepers distributing water, said UNAMID spokesman Kemal Saiki. That attack took place about 40 miles south of el-Fasher, the capital of northern Darfur.
In the other attack, which took place Friday near a market and a government checkpoint, gunmen fired on a convoy of Rwandan peacekeepers escorting a water tanker near the northern town of Saraf Umra. The force fired back, wounding an assailant, but the attackers escaped, Saiki said.
The attackers' motives are unclear, but they might have been trying to steal the troops' vehicles, he said.
"We are urging the authorities to spare no effort to conduct an inquiry and bring those (responsible) to justice," Saiki said.
The attacks bring to 22 the number of peacekeepers killed since the joint force deployed in January 2008.
The most deadly attack occurred in July 2008 when at least 200 assailants on horseback and in SUVs mounted with guns ambushed a police and military patrol, killing seven peacekeepers and wounding 22.
Violence has decreased in recent months in Darfur. The fighting began with a rebellion by ethnic African tribes accusing the Arab-dominated government of neglect. It quickly escalated into a frenzy of bloodshed with the intervention of a pro-government militia that has been accused of atrocities.