Gunmen ambushed a United Nations peacekeeping team Saturday in Sudan's western region of Darfur, killing seven and wounding another 17 in the deadliest ever attack single attack on the international force in the country.

The assault included sustained heavy fire from machine guns and possibly rocket-propelled grenades, targeting the force some 25 kilometers (15 miles) west of the town of Khor Abeche, U.N. forces spokesman Chris Cycmanick said. Reinforcements later arrived to rescue the wounded, which included two female police advisers, the force said in a statement.

No group immediately claimed responsibility for the assault. Cycmanick declined to give the nationalities of those killed and wounded in the attack.