A tornado sparked chaos near the Canadian capital Ottawa on Friday, injuring dozens as homes were damaged, cars flipped over, and over 130,000 people left without power, local media said.

Canadian federal police announced Friday the arrest of a Somali national in the 2008 kidnapping of Canadian and Australian journalists.

Ali Omar Ader had been in Ottawa for "a few days" before he was taken into custody by Royal Canadian Mounted Police national security unit.

Canada's high court Thursday rejected Ottawa's bid to treat former Guantanamo detainee Omar Khadr, who was just 15 when he was captured on an Afghan battlefield, as an adult criminal.

The government had brought the legal challenge to prevent Khadr's transfer from a Canadian federal penitentiary to a more comfortable provincial correctional facility for petty criminals and young offenders.

Lawmakers passed a bitterly opposed anti-terror law Wednesday dramatically expanding the powers and reach of Canada's spy agency, allowing it to operate overseas for the first time. 

The move came in response to the first terror attacks on Canadian soil last October, when a gunman killed a ceremonial guard and stormed parliament, and a soldier was run over in rural Quebec.

Canadian lawmakers voted Monday to extend a campaign of airstrikes against the Islamic State group and for the first time strike at them in Syria as well as in Iraq.

Prime Minister Stephen Harper's Conservatives, wielding a majority in the House of Commons, pushed through a motion on enlarging the mission in a vote 142 to 129, despite opposition parties' vigorous objections.

Federal police Tuesday arrested a Canadian with ties to the Islamic State group for allegedly helping others join the jihadists, Canadian authorities said.

International warrants were also issued through Interpol for the arrest of two other men, including a Canadian reportedly killed in Syria, for joining the banned terror group.

Police arrested an American biochemistry professor at an Ottawa hotel Wednesday over an alleged chemical threat that prompted authorities to evacuate the building, police and media reported.

"We apprehended a male at the Chimo hotel without incident," a police spokeswoman told AFP.

Australia on Tuesday raised the terrorism threat level against the police force to high for the first time, saying there were small but growing numbers of citizens involved with jihadist groups and intent on attacks.

Australian Federal Police said the decision had been taken based on intelligence-gathering and discussions with partners and was in line with the broader threat for the country, also raised to high in September.

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.