Over 1,000 civilians were killed when a Sudanese paramilitary group took over a displacement camp in Sudan's Darfur region in April, including about a third who were summarily executed, according to a report by the UN Human Rights Office on Thursday.

"Such deliberate killing of civilians or persons hors de combat may constitute the war crime of murder,” said the UN High Commissioner for Human Rights Volker Turk in a statement accompanying the 18-page report.

The Zamzam camp in Sudan's western region of Darfur housed around half a million people displaced by the civil war and was taken over by Rapid Support Forces between April 11-13.