Officials said two South Sudanese working for the UN and a compatriot working alongside the Kenyans for a water drilling company were also killed. UN Secretary General Ban Ki-moon has said the attack could constitute a war crime.
SEE ALSO :Man with nine livesThe eastern state of Jonglei has been the scene of widespread ethnic conflict since South Sudan became independent in July 2011, with bloody battles between rival tribes, including the Dinka, Lou Nuer and Murle people. Amid renewed clashes between ethnic groups and government forces, UN troops have recently bolstered troop numbers in the region and stepped up patrols. An Indian soldier was shot and wounded in Jonglei in March amid high tensions about an imminent government crackdown on rebels, while the army shot down a UN helicopter in December by mistake, killing all four Russians on board. The UN originally said some staff remained unaccounted for, but all were later found. Much of the trouble has been in Pibor county, where the UN peacekeeping force is based.