Member of Parliament David Mayo told the BBC that a hospital in the village of Lorema was attacked by soldiers and that fighting was still going on Friday.
After attacking the hospital, the soldiers set fire to local homes, Mayo said.
However, the state's governor has denied the reports of violence and said soldiers were sent to the area to protect civilians after eight of the governor's bodyguards were killed in the area. The bodyguards were working on locating cattle thieves in the area.
Since South Sudan gained independence in 2011, its army has been accused of carrying out abuses against civilian populations on numerous occasions, the BBC said. The army has denied such allegations.