MINNEAPOLIS (AP) — A registered nurse has pleaded guilty to stealing painkillers meant for patients at a Twin Cities hospital.

The U.S. Attorney’s office says 31-year-old Maria Anne Mihalik of Superior, Wis., pleaded guilty Wednesday to one count of obtaining a controlled substance by fraud.

Prosecutors accused Mihalik of entering patients’ rooms at Mercy Hospital in Coon Rapids last May and taking the painkiller Dilaudid.

Mihalik didn’t work at the hospital, but police say she was wearing scrubs and an ID badge in an attempt to blend in with other hospital workers.

She faces a potential maximum penalty of four years in prison. A sentencing date has not been set.

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