Four Nigerian peacekeepers were killed in an ambush in Darfur.
Eight more soldiers, from the joint UN-African Union peacekeeping mission Unamid, were injured when their convoy was attacked on Tuesday.
"They were providing administrative and logistic support and they were moving from one of our camps to the other," said the spokesperson for Unamid, Chris Cycmanick.
"From what I can remember I think this is probably one of the deadliest days that we've had in terms of losing peacekeepers."
The US has condemned the attack and said it was “appalled” by the violence.
"The United States is deeply concerned by the sharp deterioration in security in North Darfur and adjacent parts of Jebel Marra, Sudan," State Department spokeswoman Victoria Nuland said.
Over 16,000 Unamid troops are currently deployed in the region and tasked with protecting civilians.
Around 78 of the peacekeepers have been killed since they were first deployed in 2007.
