The medical charity, Medicine Sans Frontiers, has resumed its operations in Aburoc area in Fashoda state.
Last week, it suspended activities in the area due to clashes between government and opposition forces.
The MSF head of mission, Jaume Rado, says civilians who had fled have started returning back after the security situation improved.
He says the organization has opened its emergency service center and some of the medical staff are already working there.
“Yesterday [Tuesday] we managed to finally send back our team of international staff,” Mr. Rado told Eye Radio. “So, we are now with the whole team, back in Aburoc.”
However, he said the humanitarian situation of the IDPs remain dire with challenges of inadequate clean water, food and other basic supplies.