Gunmen have killed two African Union peacekeepers and critically wounded a third in Darfur, the African Union said in a statement Wednesday.

The peacekeeping mission said it was "deeply concerned" by the fact that the gunmen are believed to belong to the Sudan Liberation Army, the rebel faction that signed the Darfur Peace Agreement last May.

"This deplorable and condemnable act was perpetrated by gunmen believed to be elements belonging to Sudan Liberation Movement or Army (Minni Minnawi faction), which is in full control of Graida," the statement said, referring to the leader of the SLA who signed the agreement and the Darfur town where the attack took place.

The statement said that gunmen abducted the two peacekeepers while they were "on administrative duty" Monday and subsequently killed them.

"A third soldier was critically injured," the statement said, without giving details of how the attack was carried out.

Earlier Monday, about 30 gunmen belonging to the Minnawi faction surrounded an office for the implementation of the peace agreement in El Fasher, the capital of North Darfur, and "threatened the officer-in-charge," the statement said.

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