The United Nations is warning of an “unfolding humanitarian emergency” at an Australian refugee detention center on Manus Island, in Papua New Guinea. The Australian government officially closed the detention center on Tuesday, cutting off water and electricity. But hundreds of asylum seekers are still at the center, where food, water and medicine are growing scarce. The asylum seekers are refusing to leave, saying they fear for their lives if they go along with the government’s plans to relocate them to a nearby city where refugees have been attacked by men armed with knives and screwdrivers.