OTTAWA -- Canada's spy agency is eyeing the threat of a homegrown anti-Islam movement spreading online.

The Canadian Security Intelligence Service advised the office of Public Safety Minister Steven Blaney of its concerns during a secret September briefing.

CSIS flagged well-known warnings of the persistent menace posed by terrorist groups al Qaeda, Hezbollah and the more violent and radical Islamic State of Iraq and the Levant, or ISIL, say notes obtained through the Access to Information Act.

But under the heading Domestic Extremism, the spy service also underscored what might be the flip side of that coin -- the recent development "of a Canadian online anti-Islam movement, similar to ones in Europe."

CSIS characterized it as an "ongoing risk, particularly as its proponents advocate violence."

The Sept. 18 briefing for Blaney's office came a little more than a month before soldiers were killed in Canadian attacks just two days apart -- murders committed by young men that authorities say were motivated by Islamic extremism.

Shortly after the killings, there was vandalism of mosques in Ottawa and Cold Lake, Alta., threats against the B.C. Muslim Association, and a general increase in reports of public bullying and harassment of Muslims.

However, CSIS is likely more interested in the kind of anti-immigrant, anti-Islam sentiment that has taken root in some parts of northern Europe, even among the middle class, said Lorne Dawson, a University of Waterloo sociology professor and co-director of the Canadian Network for Research on Terrorism, Security and Society.

"They're just not used to dealing with immigrants at all, let alone immigrants that are quite different," Dawson said of Europe. "We have a much longer track record of immigration in general -- waves and waves of immigrants that have come for decades."

Dawson suspects CSIS is motivated by the horrific July 2011 slaughter of 77 people in Norway by Anders Behring Breivik, who penned a manifesto outlining his far-right ideology, including an extreme anti-Muslim outlook.

"In Europe, it tends to attract violent individuals. So if (there's) any chance it's starting to take wings in Canada, then you can see why they're concerned," he said. "I suspect they're just seeking due diligence to be on top of this at the earliest possible moment in light of Breivik."

A Norwegian official briefed CSIS shortly before the release of an inquiry report that found the Scandinavian country's security services could have prevented Breivik's attack.

CSIS spokeswoman Tahera Mufti did not respond to requests for comment.

A simple online search quickly turns up websites with Canadian domain addresses spouting anti-Islamic invective.

The government's anti-terrorism bill, to be scrutinized at a Commons committee starting next week, would give the RCMP power to seek a judge's order to remove extremist propaganda from websites.

National security threats are not confined to Canadian borders, the CSIS presentation notes warn.

"International developments have a considerable impact on Canada's interests."

CSIS faces a challenging investigative environment in which the rapid movement of people and modern communications technology has "extended the reach" of those who pose a threat and has increased the ease and speed with which they can act, the notes add.

"Co-operation with domestic and foreign partners is critical, including reliable access to information."