Duelling demonstrations by a small group of secular charter supporters and a group of anti-racism protesters turned violent after a man was attacked with picket-sign sticks.
Two men from opposing sides got into an altercation that led to the anti-racism protester getting attacked with wooden sticks.
The site of the protest, Collège deMaisonneuve, made headlines last month when it was reported that five of its students had left the country to join jihadists in Syria.
One of those students had also attended at least one class taught at École des compagnons, an Arabic school run by Adil Charkaoui that rents out several of the college's classrooms.
Duelling protests get tense
Tensions boiled over on Sunday afternoon outside of the CEGEP, a Quebec post-secondary school.
"If defending my liberty and condemning Sharia law is being racist, then I'm racist," said one protester in French.
"No you're not. You're a Quebecer," a fellow anti-radicalization protester told him.
A couple of dozen people who said they supported Quebec's failed secular charter — a proposed bill that would have imposed rules on head coverings in Quebec — ultimately showed up at the school. About 50 people from the anti-racism camp were there to denounce them.
"They were saying racist things about Muslims [on their Facebook page], and we had to come here and tell them that we refuse such speech in the Collège de Maisonneuve," said Collège de Maisonneuve student association spokesman Rafik Bentabbel.
Accusations of terrorism rang out among the anti-Islamization protesters, while speculation circulated wildly about what, exactly, Charkaoui was teaching at his school.
Charkaoui himself is a controversial figure. In the past, the Muslim-Montrealer had been detained by the Canadian government on a security certificate he later was successful in quashing.