The UN Security Council on Sunday condemned an ambush on UN and Africa Union troops in Sudan's Darfur region that killed seven peacekeepers.

A unanimous statement from all 15 members of the security council "in the strongest possible terms" condemned Saturday's attack on a patrol of troops with UNAMID -- the AU-UN mission in Darfur.

The council called the attack "one of the most severe attacks on UNAMID since its deployment" in 2007.

The seven dead were all Tanzanians. Seven other peacekeepers and police were injured, two seriously, UN officials said.

The council statement urged the Khartoum government "swiftly to investigate the incident and bring the perpetrators to justice."

The United Nations has made similar calls after attacks on its peacekeepers in Sudan, but UN sources say they are unaware of anyone having been held accountable.

About 50 peacekeepers belonging to UNAMID, which has some 20,000 police and soldiers under arms, have lost their lives since its deployment more than five years ago.

Rebels in Darfur have been fighting the government for a decade, but UNAMID says clashes between rival tribal and ethnic groups have been responsible for most of the worsening unrest there this year.

UN experts, human rights activists and tribal leaders have accused government security forces of involvement in this year's tribal fighting.