A day after a sometimes violent Montreal protest ended in a series of street fires, police were criticized for pepper-spraying patrons at a nearby bar patio.

Surveillance footage shows several people on the St-Bock Brasserie terrace being sprayed at close range by police in riot gear.

As other customers at the St-Denis Street bar scurry inside, an officer barrels through a tangle of tables and chairs.

Another video from a local TV station shows the officers took action after one was hit by a chair that someone threw. The chair was then flung back toward the patio.

"About one foot from the faces of my clients, police also threw this," said bar owner Martin Guimond, holding up an empty muzzle blast.

"They created panic, they destroyed the terrace and people scrambled inside, throwing themselves over each other. Everyone left without paying."

A waitress told him to call 911, then said, "But wait, it's the police that are doing this," Guimond recounted.

"That's when you realize there's a total breakdown of order."

Police said Sunday that a large object was thrown at officers passing by the bar, and that they are investigating the altercation.

The incident took place steps away from an intersection in the Latin Quarter where protesters lit several bonfires on Saturday night.

Saturday mayhem 'predictable'

The Saturday night march came as Quebec's controversial Bill 78 took effect, imposing strict rules for demonstrations involving more than 50 people.

Intended to restore order and settle the three-month-old student crisis, Bill 78 requires protest organizers to provide eight hours of warning for events, including a detailed itinerary, or be subject to heavy fines running into the thousands of dollars.

The Liberal government's legal solution to its tuition hike conflict has had the opposite effect, fuelling the growing student movement.

Gabriel Nadeau-Dubois, the movement's most prominent leader, called Saturday's mayhem unfortunate but predictable.

"It's a direct consequence from the adoption of the law," he said. "We repeated when the law was adopted that it would create a lot more anger and confrontation — and that's exactly what happened."

Nadeau-Dubois said members of the umbrella student group CLASSE are discussing how they should react to Bill 78 in future protests.

A demonstration was held Sunday afternoon against Quebec's new emergency law and another march was planned for later in the evening.

Celebrities outside Canada are getting behind the cause. Activist and filmmaker Michael Moore weighed in on Twitter in support of the students and against the new legislation.

Members of Montreal band Arcade Fire wore the movement's iconic red square during an appearance on Saturday Night Live with Mick Jagger.

Last week, darling Quebec filmmaker Xavier Dolan wore the red square on the red carpet at the Cannes Film Festival.

Bill 78's future enforcement unclear

It remains unclear to what extent police will enforce the new law — or whether they even can.

On Saturday, Montreal police appeared to take a tougher stance than previously seen during the nightly marches.

Sixty-nine people were arrested, including nine who were charged with criminal offences — five with armed aggression against police, three with assaulting police and one with arson.

The remainder of those arrested face fines for violating various bylaws.

Two police officers suffered minor injuries from projectiles, and Ouimet said that one protester also suffered a minor injury while being arrested.

He said the property damage included two police cruisers that had their windshields smashed.

Student groups aren't taking any chances with some aspects of the legislation. Several student websites had already removed schedules of future protests.

The schedules later showed up on a separate website, with a warning discouraging people from attending.

Exclusive video of pepper-spraying from CBC's French-language service: