The United Nations has issued a report on killings and displacement carried out on a “massive scale” in South Sudan. Since violence between warring factions erupted in December, more than one million people have fled their homes and thousands have been killed. The report finds civilians have been directly targeted; in one case, more than 300 men from the Nuer ethnic group were rounded up and slaughtered. Amnesty International also issued a report on the crisis Thursday, saying ethnically motivated atrocities on both sides of the conflict constitute war crimes and crimes against humanity.