Demonstrators and police clashed in downtown Montreal Wednesday after student group leaders abandoned talks with Quebec's education minister aimed at resolving an impasse over the government's proposed tuition hikes.

More than 10,000 students marched in the city's core after leaving Parc Emilie-Gamelin, where a demonstration began at 8:30 p.m. Police declared the protest illegal just before 10:30 p.m. and used stun grenades and chemical irritants to disperse the demonstrators.

According to the Montreal police Twitter account, protesters also set fire to a car at the corner of Stanley and Ste-Catherine streets.

Police said cars have been splashed with red paint during the demonstration, and protesters threw rocks at banks along their route, smashing windows at at least five banks.

CBC's Dan Halton reported that police charged the protesters with little or no warning in some cases.

Figures on the number of arrests and injuries were due to be released Thursday morning, police said.

Talks called off

The leaders of Quebec's CÉGEP and university student federations called off talks with the Liberal government, after it expelled the movement's most militant faction.

The FECQ and the FEUQ announced their decision to abandon the talks, just as negotiations were set to resume Wednesday with Education Minister Line Beauchamp.

That decision was sparked by Beauchamp's announcement that the student group CLASSE was being expelled from the discussion table. The minister blamed the group for a violent demonstration Tuesday night in Montreal.

During that demonstration, a bank window was smashed, a police officer was injured and three people were arrested.

Beauchamp said the demonstration happened despite a so-called "truce" with student leaders and called it “unacceptable."

She also accused CLASSE of using inflammatory language on its website to promote other demonstrations, including one scheduled for Wednesday night.

The president of Quebec's CÉGEP Federation, Léo Bureau-Blouin, said the breakdown in talks will not go over well with students.

"I think it's going to have negative consequences on the climate in Quebec. I think it's going to frustrate students hoping for solutions," he said.

Student leaders are denouncing violence, but are urging the education minister to "see beyond" a few violent acts, restart talks, and bring an end to the 10-week old conflict.