'Mass ethnic killings' in South Sudan

24 December 2013 Last updated at 12:35 GMT

New evidence is emerging of alleged ethnic killings committed during more than a week of fighting in South Sudan.

The violence follows a power struggle between President Salva Kiir, a Dinka, and his Nuer ex-deputy Riek Machar.

A reporter in the capital Juba quoted witnesses as saying more than 200 people, mostly from the Nuer ethnic group, were shot by security forces.

James Copnall reports.