Police in Montreal arrested dozens of protesters before Sunday's Grand Prix, as students rallying for months over tuition hikes used the Formula One event to highlight their plight.
Police spokeswoman Annie Lemieux said about 30 arrests made on Sunday morning were pre-emptive in nature, and another six people were charged with criminal offences including "intimidation and threats made to police".
Shield-wielding riot police had also pushed back and chased hundreds of protesters amassed in the downtown shopping district late on Saturday, making 28 arrests and shoving several demonstrators, some in masks, to the ground.
Protesters - mixed in with thousands of race fans and passers-by - booed and cursed before confronting police, who shouted and unleashed pepper spray. Sirens blared and people occasionally screamed from the panic of being crushed.
For four months, students, joined by anti-capitalists, have held protests against plans by the Quebec provincial government to increase tuition fees by 75 percent.
"We are in a real social crisis in Quebec. And at the moment we are witnessing police brutality, for no purpose really," University of Montreal student Zac Daoust Lefebvre told AFP.
Negotiations between student groups and the province have broken down, and the protest movement has since morphed into a larger campaign of perceived government corruption, mismanagement and injustice.
Student groups were eager to take advantage of the expanded media presence and international visitors in Montreal for Sunday's Grand Prix - won by Britain's Lewis Hamilton - to publicise their tuition fight.
Police responded with a bigger footprint, deploying numerous officers in the metro system and around the Circuit Gilles-Villeneuve with sniffer dogs to search bags and check identification documents.