Four Nigerian peacekeepers with the African Union-U.N. Mission in Darfur were killed during an ambush in Darfur. Eight other members of the UNAMID mission were injured.
A spokesman for U.N. Secretary-General Ban Ki-moon said the United Nations was calling on the Sudanese government to conduct a thorough investigation into the attack to ensure the perpetrators are brought to justice.
The Security Council issued a statement saying it condemned the attack "in the strongest terms."
The peacekeeping mission said it was attacked with heavy fire from "several directions" in West Darfur. UNAMID forces returned fire during the barrage, the mission added.
The U.S. State Department mid-September advised U.S. citizens to avoid traveling to Darfur or the Sudanese states of Blue Nile and South Kordofan. The warning said the threat level in Sudan, particularly in Darfur, "remains critical."