BISMARCK — An incident described as a "staff assault" last week at the North Dakota State Penitentiary involved one male inmate and one male staff member, officials said Monday, July 8.

The July 2 incident happened in the kitchen of the Bismarck prison, state Department of Corrections and Rehabilitation spokeswoman Kayli Richards said.

She declined to say whether the staff member sought medical treatment, citing privacy. She also declined to release more details, citing an ongoing investigation.

"Once the investigation is complete, (Corrections) will forward on the investigation to the Burleigh County state’s attorney," Richards said. "It’s at their discretion whether charges will be brought forth."

The prison was put on lockdown twice in January when seven correctional officers needed medical attention after being injured during assaults.