Four U.N. peacekeepers have been shot and wounded in southern Sudan while on patrol close to the disputed town of Abyei.
U.N. spokesman Farhan Haq said the Zambian peacekeepers were evacuated for immediate medical treatment after Tuesday's shooting and their condition was not immediately known.
He said the identity of the attackers has not been determined.
The patrol was heading from Diffra to Abyei and the attack took place near Gali, Haq said.
The U.N. has some 9,000 troops and 700 international police officers enforcing a 2005 peace deal that the civil war between the ethnic African south and Sudan's Arab-dominated government.
The U.N. condemned the attack and Haq said an emergency meeting of military officials from both sides and the U.N. would be held Wednesday.