The Independent Investigation Unit is looking into the alleged assault by an on-duty Manitoba First Nations Police Service officer.
The IIU says the reported incident happened on August 16 when a female, who was lodged in MFNP cells, became aggressive and force was used to secure her.
The female sustained a cut to her head and was transported to Portage District General Hospital, where she was treated and released back into custody.
Anyone with additional information is asked to contact the IIU at 1-844-667-6060.
