LINCOLN, Neb. (AP) — Authorities say an inmate has assaulted a staff member at the Nebraska State Penitentiary in Lincoln.

The Nebraska Department of Correctional Services says the assault occurred Sunday. The department says the inmate punched the staffer in the head and was subdued by other staffers using physical force and chemical agents.

The department says the staff member was taken to a Lincoln medical facility for treatment and then released.

The names of the staffer and inmate have not been released.