The United Nations says one peacekeeper in Central African Republic has been killed and another injured by armed attackers north of the capital, Bangui.

Stephane Dujarric, the spokesman for the U.N. Secretary-General, said in a statement from the U.N. Wednesday that a Central African Republic mission convoy travelling from Damara to Ngerengou came under fire on Tuesday by an unknown group about 55 kilometers (34 miles) north of Bangui. He said the peacekeepers from Burundi returned fire.

The secretary-general condemned the attack and called for swift action to bring the attackers to justice. He called on armed groups to lay down weapons.

Sectarian clashes between rival Christian and Muslim militias have flared in recent weeks, killing at least 42 people.