Frustration, disgust, and anger over the violent arrest of a skateboarder in downtown Barrie shifted from online forums to city streets Saturday.

About 40 people gathered near the spot 20-year-old Skyler Kent was arrested Thursday after running a red light on his skateboard. Demonstrators hoisted signs and skateboards as passing drivers honked their horns.

In a widely-circulated video, a Barrie Police officer struggles on the ground with Kent and holds what appears to be a stun gun while threatening to "light [him] up."

The cellphone video, recorded by a bystander, appears to show the officer hitting Kent on the head with the device as he continues to hold him to the ground.

The officer involved has been assigned to other duties pending an investigation by the Ontario Provincial Police requested by Barrie Police.

The violence moved Matt Kordy to organize Saturday's protest.

"It turned my stomach. That was just appalling to me, " Kordy said.

Kelly Platt witnessed and recorded Kent's arrest and joined Saturday's demonstration.

"I'm really not one to pull out my camera, but when I saw (Kent) go down and I heard his head hit the pavement, I knew...as a mother, I had to take out my phone."

Kent's sister Samantha Grisdale said hearing her brother call for someone to call 911 while being pinned to the ground broke her heart. She's grateful the OPP is reviewing what happened.

While the video doesn't show what happened leading up to the arrest, Skyler Kent said he rode his skateboard through a red light at Barrie's Five Points, and that's when police pulled him over.

Kent said it took 20 to 30 minutes for police to issue him the ticket, and when they did, he skateboarded away, calling the officers names as he left.

"After I left with the ticket, he put the lights on again," he said. "I tried to keep going because I figured he can't pull me over twice in a row like that, and then he slams on the brakes after getting in front of me, and I ran into the back of him."

That's when Kent said the incident that was caught on video began.

"I was resisting, but I wasn't trying to fight him. There was no part of me that was trying to hit him or hurt him.

I just didn't understand why I was being arrested for something that was a traffic violation," he said.

Kent also admitted he was arguing with police, "I'm not gonna act like I didn't have a mouth on me," he said.

Police charged Kent with causing a disturbance and assault with an attempt to resist arrest. He was released with a promise to appear and an undertaking.

CTV News asked Barrie Police Services if the officer involved was wearing a body camera at the time of the incident and was told the pilot project for body cameras ended the day before the arrest.

Demonstrators speak out against violent arrest in Barrie, Ont.