STILLWATER, Minn. (AP) — The Minnesota Department of Corrections says five staff members at the Minnesota Correctional Facility-Oak Park Heights had to be treated at a hospital after an inmate melee.

Department of Corrections spokesperson Sarah Fitzgerald tells the Pioneer Press that the workers were treated and released in the same day. The Friday night incident involving an unknown number of inmates is under investigation.

The prison is the state's maximum security facility.

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