Two South Simcoe Police officers suffered minor head injuries when they tried to arrest a suspect after they were called to an Alcona plaza around 10 p.m. on Tuesday about a fight involving 30 young people.
There were reports of a crowbar, a baseball bat and a possible firearm.
Police said a male suspect assaulted another person with a crowbar during the altercation and another victim was punched and threatened.
When they went to arrest the male, police allege the suspect refused to get out of his vehicle, resisted arrest and then assaulted the officers.
A 19-year-old from Innisfil faces a number of charges including two counts each of resisting arrest and assaulting police, and one count each of assault, assault with a weapon and uttering threats.
South Simcoe Police is appealing for witnesses to come forward. Police spoke to some people at the scene but others fled. Anyone with digital evidence in cell phone images and/or video is asked to contact police.