GREEN BAY, Wis. (AP) — The Green Bay Correctional Institution was locked down after an inmate assaulted a staff member.

The Wisconsin Department of Corrections says the assault happened Friday morning.

The employee was injured and is receiving medical care.

The Corrections Department has begun an internal investigation and referred the incident to the Brown County Sheriff’s Office.

The Green Bay Press Gazette reports the correctional institution remained in lockdown Friday afternoon as the assault was being investigated.