GENEVA (AP) — The United Nations human rights chief on Friday sounded a “red alert” about possible atrocity crimes in and near a strategic city in central Sudan, calling on world leaders to do more to help stop the bloodshed in the country’s ongoing war between the army and paramilitary forces.

U.N. High Commissioner for Human Rights Volker Türk told the Human Rights Council at the U.N. office in Geneva that signs from the city of el-Obeid were “clear and unmistakable: Another human rights catastrophe is unfolding in Sudan.”