PLYMOUTH — Hennepin County’s top prosecutor said the police officer who fatally shot a man in an Arby’s restaurant last year will not face any charges.

County Attorney Mike Freeman said it was reasonable for Plymouth Officer Amy Therkelsen to use deadly force to protect herself and people in the restaurant from a man having a psychotic episode.

Therkelsen and three bystanders struggled with Derek Wolfstellar last July inside Arby’s in Plymouth. The officer used her Taser on Wolfstellar, but authorities said it didn’t stop him from trying to take her service weapon. Therkelsen gained control of the weapon and shot Wolfstellar twice in the head.

According to reports, the attorney’s office said tests showed Wolfstellar’s DNA was on the gun holster and belt.

Wolfstellar’s grandparents told investigators that he has struggled with drug use and mental illness for years.