The province's police watchdog says a Toronto police officer is facing an assault charge over his involvement in an arrest last July.

The Special Investigations Unit says several officers from the Toronto police major crime unit attempted to arrest four men who were seen entering a vehicle in a parking lot.

During the arrest, the 24-year-old driver of the vehicle suffered a fracture to the bone around his right eye.

SIU director Tony Loparco says an investigation found reasonable grounds to believe the officer committed a criminal offence.

Sgt. Darren Worth has been charged with one count of assault causing bodily harm, and is to appear in court on Feb. 18.

The SIU is an arm's length agency that investigates reports involving police where there has been death, serious injury or allegations of sexual assault.