More than 19 people have been killed in the cattle raid at Jalle payam, Bor, Jonglei.
County Commissioner Mamer Ruk says the dead include seven soldiers and twelve civilians.
He told Eye Radio that gunmen attacked a cattle camp in a remote village in the morning and drove off with cattle.
Mr Ruk said the youth resisted, and tried to reclaim the cattle with the help of the SPLA soldiers in the area; the fighting continued until Thursday evening.
He suspected that the gunmen came from Pibor and warned the death toll could be higher.
“Up to now, we have a number of the people who are still missing, including the head of mission of the SPLA,” he said.
It is unclear how many of the attackers were killed.
Authorities from Pibor are yet to comment. However, when such accusations were made in the past incidents, the authorities there said they would verify the accusations and arrest the suspects.