Having got through the Bahrain Grand Prix weekend with only its ethics damaged, Formula One must have thought that from here on in the only trouble it faced this season would be from on-track clashes, stewards decision and the usual political wrangling between the team bosses and the sport's powers that be.

However, as we reported at the start of the week, though not comparable to the situation in Bahrain, civil unrest threatens to disrupt the Canadian Grand Prix.

On Wednesday night over 500 protestors were arrested, the largest number of arrests since the action began.

At the heart of the unrest is the fact that students are unhappy at a planned hike to their tuition fees. However, the ill feeling has now expanded into wider social issues with, as a Pitpass source claims; "lines being drawn right down every divide there is, old and young, urban and rural, Anglophone and Francophone".

"It's nastiness of nationally historic proportions," they added.

The police action that outlaws demonstrations has only made the situation worse and night by night the crowds get bigger.

As the US government warns Americans heading to Montreal about "unforeseen violence, vandalism and "arrests", the Canadian Press reports that: "The world is becoming increasingly aware of the social tumult, which has begun to affect the province's interactions with outsiders in a variety of ways.

"Foreign newscasts are carrying Montreal scenes of streets ablaze and billy clubs being swung, while prestigious newspapers abroad are carrying analysis of the conflict.

"Tourists have been hassled, even detained, by riot police. Some are reconsidering whether to travel to Montreal for the city's upcoming Canadian Grand Prix."

Wednesday saw the thirtieth consecutive night-time march by protestors, thought to number around 3,000. While peaceful at first, things "turned ugly" when police surrounded a large group of protesters to make a mass arrest.

Montreal police Constable Daniel Fortier revealed that of the 516 arrested - including 30 minors - one person had been arrested for wearing a mask, this having been made illegal under a new anti-mask law.

Worryingly, in terms of the Grand Prix, Montreal anti-capitalist activist Jaggi Singh, took to Twitter to proclaim: "Grand Prix website brags about 'jet set' coming to Mtl" and "Rich douchebags are going to be disrupted by night demos". He later tweeted that if Montreal's "capitalist class" is worried about the disruptions of Grand Prix parties, "then maybe there should be disruptions!"

Meanwhile, Gilbert Rozon, president and founder of Montreal's Just for Laughs comedy festival, told the National Post that he is worried the race could become a target. "This is a debate about left and right," he said, "and the Grand Prix is about big cars and rich people, so I suppose they are very nervous."

Just two weeks before the F1 circus comers to town, Ziggy Eichenbaum, owner of Ziggy's pub on Crescent Street, told the National Post that his takings are down by as much as 20%. "A lot of the regular customers, when they finish their work they just go home because they don't want to stick around downtown," he said. "They're worried if there's a demonstration they'll get stuck until midnight."

Looking ahead to the race week, he added: "What about the shops who are counting on (the) Grand Prix to keep them above water?" This is the week that makes them or breaks them."