TORONTO -- An Ontario provincial police officer has been charged with assault after an incident in Toronto that left a 19-year-old Oshawa, Ont., man with a concussion.

The province's police watchdog says the man was driving just after midnight on July 1 when he experienced car trouble and pulled over on the shoulder of Highway 401.

The Special Investigations Unit says two officers were called to the scene and the man was hurt during the interaction.

The SIU says he was later diagnosed with a concussion.

The agency says it has reasonable grounds to believe one of the officers assaulted the man.

OPP Const. Scott Hearnden is charged with assault causing bodily harm and is due in court on Feb. 10.