Canadian Prime Minister Justin Trudeau on Sunday condemned the violence and "despicable rhetoric" that marked several weekend protests throughout the country, after clashes between pro-Israel and pro-Palestinian protesters in Montreal.

The Canadian city of Montreal on Friday declared a state of emergency over the threat of flooding following a similar decision by the capital Ottawa.

An Air France flight from San Francisco to Paris was diverted to Montreal "as a precaution" after an "anonymous threat," the airline told AFP on Tuesday.

Flight AF083 from San Francisco to the main Paris airport of Charles de Gaulle touched down just before midnight local time in Montreal, the firm said.

Canadian police arrested 10 young people as they allegedly tried to leave the country to join the Islamic State group, the Royal Canadian Mounted Police said Tuesday.

The federal police arrested the group, all residents of the Montreal area, last weekend at the city's international airport and their passports have been withdrawn.

Canada arrested three men on terrorism-related charges in as many days because they represented a "serious" potential threat, the country's top public safety official said Tuesday.

"If accusations are laid, it's because there's a serious reason to believe they are potential terrorists," Public Safety Minister Steven Blaney told CBC television.

Royal Canadian Mounted Police said two brothers have been arrested and charged with terrorism related offences.

In a statement police said that Ashton Carleton Larmond and Carlos Larmond, both 25, were planning to leave Canada to engage in terrorist activities abroad.

Hundreds in Washington, New York and Canada rallied Wednesday night in the frigid cold proclaiming "I am Charlie" in solidarity with those killed in a deadly attack on French magazine Charlie Hebdo.

Some 200 to 300 French and American protesters gathered in the nation's capital in front of the Newseum, a museum dedicated to news, waving signs and French flags emblazoned with the now ubiquitous rallying cry "Je suis Charlie."

A fierce winter storm has caused chaos in the United States since the start of the year, killing 11 people, canceling thousands of flights and bringing freezing temperatures to Canada.

Northeastern U.S. states felt the biggest impact, with more than 24 inches (61 centimeters) of snow falling in parts of a Massachusetts town and a state of emergency being declared in New York and New Jersey.

Thousands of mostly Muslim protesters took to the street in Montreal to express anger Saturday at a plan to ban public sector workers from wearing religious garb in Quebec.

The prohibition of headscarves, turbans and other religious garments is part of a proposed overhaul of the Canadian province's "Charter of Values."

A Muslim youth conference criticized by the Quebec government was canceled Saturday by the Montreal convention center where it had been set to take place.

The Palais des Congres said it canceled the "Entre Ciel et Terre" (Between Heaven and Earth) conference after a "security review." It had been set to take place September 7-8.