Most of the 150 locally hired staff at Doctors Without Borders clinics in South Sudan have vanished since fleeing heavy fighting, the group said. Two healthcare facilities operated by the medical humanitarian organization were targeted in attacks in Jonglei state in Pibor County, forcing the suspension of medical activities, the organization said Tuesday in a release. Ten international staff members were relocated to Juba just before the violence and 156 locally hired staff were advised to leave their town or village and seek refuge, Doctors Without Borders said. Although the organization established contact with a few of them, officials said many of the local staff can\'t be reached. \"Thousands of people in Lekongole and Pibor fled in the last week and are now hiding in the bush, frightened for their lives,\" said Parthesarathy Rajendran, the head of mission in South Sudan. \"They fled in haste and have no food or water, some of them doubtless with wounds. Now they are hiding on their own, beyond the reach of humanitarian assistance.\" During the end-of-the-year violence, Doctors Without Borders medical facilities in Likongol and Pibor were looted and damaged. A third clinic in Gumuruk has apparently wasn\'t affected, the organization said. The organization said the facilities were evacuated as fighters from the Lou Nuer tribe moved closer in the area, Bikyamasr.com reported. The Lou Nuer and Murle tribes have accused each other of stealing cattle and killing tribal members.