The SIU is investigating an incident in Orillia in which a police officer and a civilian were injured.
The OPP were called late Wednesday night to a restaurant on Memorial Avenue to deal with a person who refused to leave.
When the encounter was over an officer and the person being investigated had been injured.
A 35 year-old Orillia man faces several charges including assaulting a police officer causing bodily harm, resisting police, and escaping lawful custody.