Eighty-five people have been arrested during violent demonstrations in Montreal over rising tuition fees.
Police used pepper spray to quell the protest, during which windows of banks, businesses and cars were smashed.
Six people were injured in the riot, which flared as talks between student groups and the government broke down.
Students have been protesting for 11 weeks over plans to increase university fees by C$325 (£200) per year over five years.
The government said the talks had ended because Classe, a student group, had not halted its street protests, a condition for negotiations.
'Oil on the fire'
After Classe was expelled from the talks, other student groups also left the negotiating table.
Gabriel Nadeau-Dubois, spokesman for Classe, told CBC News after the talks broke down: "All this does is pour oil on the fire."
On Thursday, Mr Nadeau-Dubois said Classe did not "encourage violence, have never encouraged violence and I don't encourage violence".
But Education Minister Line Beauchamp said: "I regret that this Classe has chosen its camp."
"There will be no dialogue [with them] as long as the violence continues," Quebec Premier Jean Charest said on Thursday.
Leo Bureau-Blouin, president of the college student federation, accused Mr Charest of shutting down talks deliberately.
"With the breakdown of discussions, he knew it would spark protests," Mr Bureau-Blouin told the Globe and Mail newspaper. "So I think the Quebec government is playing a dangerous game with public opinion as part of its re-election."
Separately, Montreal's mayor and police chief held a press conference urging calm and demanded a resumption of talks.
The government of Quebec has made no indication that it would reconsider the proposed rise in tuition fees.