The Office of The Police Complaints Commissioner ordered the West Vancouver department to step in after video of the arrest spread across the Internet.
The video shows Const. Ismail Bhabha punching a man he was attempting to put into handcuffs during an arrest in Vancouver Mar. 25.
The officers involved said they were trying to arrest Andi Shae Akhavan because he rode his bicycle through a red light and wasn't wearing a helmet.
The complaint commissioner's office has determined it's in the public interest to investigate the allegations against the officer.
The office said it learned of the incident through the media, and when the office contacted the Vancouver Police professional standards department, it didn't know about the punch either.
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