The head of CSIS, the Canadian Security Intelligence Service, warned Monday that Canadians are involved in every al-Qaeda affiliate group and that these groups have mentioned Canada as a possible target.

Richard Fadden appeared before the Senate Committee on National Security and Defence in Ottawa. He told the committee the threat posed by al-Qaeda is changing and becoming harder for authorities to track.

"Al-Qaeda in the [Afghanistan/Pakistan] area was the directing brain that caused 9/11. It has been much weakened," Fadden said.

"But on the other hand, all of their affiliates…..they are much, much more operational than they used to be, They are beginning to communicate between themselves far more than they used to. And in every single case, there are Canadians who have joined them," he said.

"CSIS is currently aware of dozens of Canadians — many in their early 20s — who have travelled or attempted to travel overseas to engage in terrorism-related activites in recent years," he told the committee.

"I think the threat remains roughly at the same level. But it has morphed, though, into something that’s harder to get your hands on."

Smaller acts of violence

Fadden says Canadians who join militant groups do so for many reasons.

"You have a range of people who want to seem self-important among their own groups, to other people who are motivated by a deep sense of religious wrongdoing. I think in the middle, where we’ve found most of the people, it’s largely individuals who feel that the Muslim world is under attack and that somehow Canada is contributing to that."

Fadden told the committee al-Qaeda has switched tactics over the years. The group, he says, used to work toward "big bang" attacks like 9/11. Today, he says, it aims to carry out smaller acts of violence through affiliate groups or even individuals.

"It is slightly more difficult to get our hands on these cases," Fadden said. "But there are fewer plans for really big incidents."

Fadden’s comments come as the federal government tries to establish the facts around two high profile attacks overseas in which Canadians are believed to have been involved.

The government of Algeria claims Canadians took part in an attack on an oil facility in that country. Meanwhile, investigators in Bulgaria says a Canadian citizen helped carry out a deadly attack on a tourist bus in that country last year that killed five Israeli tourists and a bus driver.

Security tightened after Delisle case

Fadden touched on other topics during his appearance before the Senate committee, including cybersecurity and the case of convicted spy, navy Sub-Lt. Jeffrey Delisle.

The CSIS director says that even though the Delisle case has led to increased security in many government departments, he can’t guarantee Canada or its allies won’t fall victim to espionage again.

"He (Delisle) didn’t do anything obvious that would lead either ourselves or the Defence Department to believe that he was a traitor," Fadden said.

"That’s almost always the case," he added.

"Similar cases in Australia, the United States, the United Kingdom; it’s the quiet guy who doesn’t make a fuss who often succeeds in doing this."

Cyberattacks blamed on '2 or 3 states'

On cybersecurity, Fadden blames a large number of cyberattacks on "two or three states" that "throw thousands and thousands of people at it."

"This is not an issue that security agencies can solve by themselves," he said.

"This is going to require the involvement of foreign ministries that would encourage, I think, the development of international norms somewhat similar to the laws of war in years past."

As for the role of CSIS in fending off all these threats, Fadden told the senate committee he is right now satisfied with the resources his agency is receiving. But he says that may change.

"I think our general view is that we’re okay for now," he said.

"But if cyber, in particular, continues to worsen almost exponentially, I’m not sure we’d be able to say the same thing in two or three or four years."