SURREY, B.C. -- Gerry Martin says he's surprised to see video of a fight breaking out on a Surrey, B.C., bus, allegedly over a mask.

It happened Saturday morning at about 9:30, when a man boarded a bus without one.

Police say another man offered him a face covering, and he refused. He was asked whether he had a medical exemption, and police say that's when the suspect became belligerent.

"It was a violent attack," said Const. Mike Yake with Metro Vancouver Transit Police. "This is the first time on the transit system that we have seen a level of violence due to the mandatory mask policy."

Witnesses recorded the fight on the 312 bus in Surrey on cellphones.

Police say the suspect is the man in the black sweater seen in their videos.

"He appears to be a South Asian male, possibly in his mid-20s to early 30s and at the time he was wearing a black sweater with 'Puma' writing on it," said Yake.

"That's crazy," Martin said to CTV News after watching the video. "I approached (someone) myself about a week and a half ago."

But his experience was very different.

"It was good. I feel good about it," Martin said. "He was the only one on there without one, and he wished he had a mask, so it went well."

But looking at the video, Martin said he realized it easily could have gone wrong.

"I shouldn't have taken that on."

The victim of Saturday's incident was taken to hospital for a cut above his eye, but police told CTV News he has since been released.

Yake said the investigation is still in its early stages, but in terms of charges, "at the very least we're looking at an assault."

Adeeb Baig takes transit regularly and said he's surprised things escalated so quickly.

"He shouldn't have been fighting him but basically everyone's a little frustrated right?"

Baig said instead of approaching someone without a mask, he keeps his distance.

"It's on them if they don't want to wear a mask but all we can do is really distance ourselves," said Baig.

That's what transit police and TransLink want riders to do. Don't approach someone without a mask. Instead, keep your distance.

Part of the reasoning is that situations can escalate, but police added passengers may not know what's behind the decision not to bring a mask on board.

"Not all medical conditions or disabilities are visible," said Yake.

The suspect left the scene Saturday after the fight ended. Transit police are asking anyone who may recognize the suspect or who witnessed the incident to come forward.