JUBA – Ten aid workers have gone missing in South Sudan’s Yei town in unclear circumstances, the U.N. Humanitarian Coordinator for South Sudan said on Thursday.

Alain Noudehou said in a statement the convoy of a mix of U.N. and other aid workers was heading to Tore from Yei, in Central Equatoria region, early on Wednesday and that their whereabouts and well-being was unknown.

“We are deeply concerned about the whereabouts of these humanitarian workers and are urgently seeking information about their well-being,” he said.