Canada has named the far-right Proud Boys a terrorist entity, saying it poses an active security threat and played a "pivotal role" in last month's attack on the US Capitol that left five dead.
Although the Proud Boys have never mounted an attack in Canada, Public Safety Minister Bill Blair said on Wednesday domestic intelligence forces were increasingly worried about the group.
"There has been a serious and concerning escalation of violence - not just rhetoric but activity and planning - and that is why we have responded as we have," he told a news conference. He did not give details.
The group's founder, Gavin McInnes, is Canadian but now lives in the United States.
US authorities have charged several members of the Proud Boys in connection with the January 6 attack in Washington.
Ottawa added 12 other groups to its list of terrorist entities - three neo-Nazi groups, eight organisations described as affiliates to al Qaeda and Islamic State, as well as Hizbul Mujahideen, a Kashmiri group.
Blair said Canadian intelligence agencies had worked for months and in some cases years to gather the evidence needed to list the groups.
"Canada will not tolerate ideological, religious or politically motivated acts of violence," Blair said.
Founded in 2016, the Proud Boys began as an organisation protesting political correctness and perceived constraints on masculinity in the United States and Canada and grew into a group embracing street fighting.
Former US president Donald Trump, asked last September whether he would denounce white supremacists and militia groups, called on the Proud Boys to "stand back and stand by".
The group's assets can be frozen by banks and financial institutions and it is a crime for Canadians to knowingly deal with assets of a listed entity.
Anyone belonging to the group can be blocked from entering Canada.
Stephanie Carvin, an assistant professor and security expert at Carleton University, said Ottawa was broadening its interpretation of the concept of terrorism, which had once mainly referred to religiously motivated extremism.
"What we're seeing now is a shift to seeing these groups (like the Proud Boys) as capable of orchestrating the kinds of violence that raise national security concerns," she said.