TORONTO -- Police are investigating an incident aboard a Toronto streetcar on Friday after video of a violent interaction involving transit constables and a passenger surfaced on social media.

The 12-second video shows what appears to be two Toronto Transit Commission (TTC) Special Constables in an altercation with a rider on a streetcar. One of the constables is seen holding the man down, pinning him to a seat. At some point in the video, the other constable appears to spray a white substance on the man.

Someone can be heard in the video saying “get down.”

According to the person who posted the video to Twitter, the incident occurred around 7:50 a.m. on a 501 streetcar on Queen Street, near River Street. The officers allegedly approached the man and asked for proof of payment, the Twitter user posted, and when the man tried to move in the opposite direction there was “mutual shoving and then punches.”

“Everything escalated in less than a second,” Twitter user @CascadingDesign said. “Some sort of pepper spray foam was used, the man was subdued and then handcuffed. Nobody else was injured or involved as far as I can tell.”

The Twitter user said that before the constables arrived on the streetcar, the man had kicked off his shoes and was yelling at people.

“If you ignored him (and up to the point of the fare inspectors getting on, everyone did ignore him) he wouldn't have been a danger to anybody,” they said.

A spokesperson for the TTC said that the incident occurred during a routine fare inspection.

“The altercation involving two TTC Special Constables took place after they were approached by several customers on board the vehicle who had concerns,” the TTC said in a statement. “We are investigating the incident.”

In a statement, Rick Leary, the CEO of the TTC, said he takes the issue very seriously.

"I have given direction to initiate an investigation by an external party," he said.

Toronto police is also investigating the matter and said they are aware of an incident that occurred Friday where a man was “reportedly acting aggressive and violent.”

“This was initially investigated by TTC Personnel who subsequently arrested a man.”

The man was transported to the Toronto police’s 51 division and police say the investigation is ongoing.

Neither the TTC nor Toronto police confirmed what substance was sprayed on the man.

Two city councilors have since commented on the video, calling the handling of the situation unacceptable.

“The actual offence, if any, doesn’t even matter anymore, “ said Councillor Kristyn Wong-Tam, who represents the riding where the incident took place. “This is not how the TTC should be treating riders. There needs to be a full investigation into this use of force, which is never acceptable.”

Councillor Brad Bradford said that what occurred was “unequivocally the wrong way to handle fare evasion.”

“Another example of why we need to improve the training and recruitment processes for fare inspectors,” he said on social media. “Officers need to de-escalate these situations, not resort to force.”