A class action lawsuit has been launched against the city of Montreal on behalf of protesters who were arrested May 23 during a mass demonstration opposing tuition fee hikes.

Lawyer Marc Chetrit has filed the case in Quebec Superior Court alleging that the city and its police department violated charter rights during the arrest and detention of more than 500 people.

"People were held with their hands tied behind their backs, with no access to water or washrooms for sometimes up to five hours. They were sometimes held for up to eight hours," said Chetrit.

In an interview with CBC Tuesday, Chetrit would not specify a dollar figure he will seek for damages as part of the lawsuit. But he said plaintiffs in a similar class action suit in Montreal, 15 years ago, were awarded $2,500 each.

Most people arrested were fined

Nightly tuition protests ramped up in Montreal after the provincial government adopted Bill 78, put in place to place restictions on demonstrations.

The law served to attract support from civil rights groups. Many groups joined students and their supporters in the streets to oppose the new law and to put pressure on the government to negotiate with students.

On May 23, Montreal authorities moved in on protesters, kettling them and arresting at least 518 people.

The sweeping crackdown by authorities marked a new single night record for arrests since the start of the tuition conflict.

The majority of those arrested in Montreal faced fines, police said.

That night, in Quebec City, police detained 176 people under the provisions laid out in Bill 78. That demonstration was declared illegal because protesters refused to give police their route in advance, one of the provisions of the new law.

Police later ticketed the detainees for blocking the roadway, under the traffic act.