Rebels in eastern Congo are threatening to view United Nations peacekeepers as hostile forces unless the world body explains its role and refrains from further attacks. The veiled threat comes only days after UN helicopter gunships bombarded several of the M23 rebels\' positions near Rutshuru in North Kivu province. In a letter to the UN Security Council, obtained by The Associated Press today, they allege that civilians were killed in the air raids, without providing an exact death toll. They say if the Security Council fails to explain the peacekeepers\' \"real mandate,\" they will assume that it has changed to make the UN an active partisan force, which would mean \"to tell our forces to set up defenses against the UN troops, their infrastructure and staffers.\" Congo has the world\'s largest peacekeeping force of some 20,000 troops.