The former Commissioner of Torit County says he has been released from detention without charges.
German Charles was arrested last week, along with 12 other former state government officials over unclear reasons.
However, he told Eye Radio that Imatong state authorities suspected that the men were behind the ambush which the commissioner of Lafon County survived last week.
The attack resulted in the killing of 12 people and four others injured, including the commissioner and one of his bodyguards.
“Up to now, there was no proper reason for our arrest; no proper discussion and we don’t know what will happen next,” Mr Charles told Eye Radio.
Efforts to reach the authorities in Imatong state for a comment were not successful.