Demonstrators in Montreal bang their pots and pans as anger grows at Bill 78, which places draconian restrictions on protests

At 8pm on Friday there were 20 people banging pots and pans near Jarry station in Montreal.

By 8.10pm, there were nearly 200, walking in circles round the intersection of Rue Saint Denis and Rue Jarry as the pedestrian crossing changed.

Ten minutes later, hundreds of protesters were in the road blocking traffic, the din from their kitchen implements drowning out the car horns.

The 'casseroles' movement sprang up in response to the Quebec provincial government's introduction of Bill 78, a controversial law introduced last week to quell student protests over tuition fee increases. The pot-banging protests began with a Facebook call out on Saturday 19 May, and have since spread to neighbourhoods across Montreal, with Jarry's contingent particularly popular on Friday.

Mark Recher, a 53-year-old musician born and raised in Montreal, was out with his pan for the first time. He said he had been driven to protest by the new legislation.

"The big games started when [the government] passed bill 78. Before that it was just the government and students," he said.

"But now: first it's 78, but after that lots of things. Quebec has had enough. And all these young people – people say university is cheap now, but these young people's taxes will be paying for us in a few years."

The Quebec provincial government introduced Bill 78 on Friday 18 May in response to growing student demonstrations against government proposals that would increase university fees by C$325 a year for five years. The legislation officially suspended university terms, in response to the class walkouts which have been observed in many institutions since February, but also placed draconian restrictions on protests.

Police in Quebec now have to be given eight hours' notice prior to demonstrations of 50 or more people. Protesters must also provide, and stick to, a strict itinerary. Individuals breaching the law can be fined up to C$5,000; student associations C$125,000.

But the bill appears to have only fanned the flames of the demonstrations, winning students larger backing from Quebec residents than they had before.

"I'm very surprised at what's happened," said Kevin Audet-Vallee, a 24-year-old history student who had attended tuition fees protests before bill 78 was introduced.

"Now that the ordinary citizens are in the streets I think the government is really in trouble, because the middle class is in the streets. At first [critics of student protesters] were saying we were radicals. These are not radicals."

Indeed, at the pot banging near the Jarry subway on Friday night the age range of the crowd was strikingly diverse. Sensibly dressed fortysomethings wearing hiking boots and kagools intermingled with long-haired students wearing only shorts. Men and women pushing young children in prams were flanked by hipsters on fixed-gear bikes.

The range of protesters was matched by the diversity of utensils they chose to create noise. Some had reached past the saucepan and wooden spoon, with the Guardian spying such unlikely pairings as a colander and a drumstick, a pan lid and a pair of chopsticks, and a barbecue lid and a pair of tongs all being put to alternative use.

As the protesters marched for more than four hours through various Montreal neighbourhoods, many people had taken to their balconies in support, bringing their own kitchenware and adding to the din.

In spite of a heavy downpour, the Jarry march picked up casseroles groups from other areas, with a limited police presence powerless to enforce Bill 78. Thousands of protesters walked along the middle of the city's streets, and officers adopted a hands-off policy, in a different strategy from earlier in the week, when protesters were kettled and arrested in large numbers.

The casserole idea was based on the 'cacerolazo' protests which were used against Augusto Pinochet and others in Chile in the 1970s. Political science teacher François-Olivier Chené suggested the idea on Facebook, according to community news website OpenFile.

"Every night, at 8pm, during 15 minutes, take a casserole or any object that makes some noise and bang it with all the wrath that Bill 78 inspires you!" Chene wrote.

"[Pinochet] decided that all gatherings of more than four people was illegal. In response to that, the citizens used their casseroles to express their anger. Let's do like they did!"

Since last Saturday different areas of Montreal have rung out to the sound of pots and pans being beaten by protesters, while daily student protests have continued, with organisers estimating some 300,000 took to the streets on Tuesday. More than 700 demonstrators were arrested on Wednesday night.

Earlier on Friday, student groups and union groups had issued a legal challenge to Bill 78, asking that it be quashed permanently. A separate motion was also filed in court requesting that sections on the number of demonstrators allowed to protest and the restrictions on student organisations be suspended.

"Thousands of lawyers worked through the night on this," said Léo Bureau-Blouin, president of the Fédération étudiante collégiale du Québec, the Montreal Gazette reported.

"It's the biggest constitutional challenge in Quebec history."