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."

Loading Slideshow...
  • Osama Bin Laden

    Al-Qaeda's Saudi leader was killed in an American raid on May 1, 2011. (AP Photo, File)

  • Ayman al-Zawahri

    Ayman al-Zawahri became <a href="" target="_hplink">al Qaeda's new leader</a> after the death of Osama bin Laden. He is believed to be hiding in Pakistan and regularly releases propaganda videos. (AP Photo/SITE Intel Group)

  • Abu Yahia Al Libi

    Abu Yahia al Libi was al Qaeda's <a href="" target="_hplink">de facto no. 2</a> after the death of Bin Laden. He escaped a high-security U.S. prison in Bagram, Afghanistan, in 2005 and <a href="" target="_hplink">was killed</a> in a strike in Pakistan in June 2012. (AP)

  • Nasser al-Wahishi

    Al Wahishi was once bin Laden's <a href="" target="_hplink">aide-de-camp</a> and now commands AQAP, al Qaeda in the Arabian Peninsula . (AFP/GettyImages)

  • Ibrahim Hassan Al Asiri

    Saudi Ibrahim Hassan al Asiri is <a href="" target="_hplink">believed to be responsible </a>for building uilding the underwear bomb used to try to bring down a Detroit-bound jetliner on Christmas 2009, as well as the printer-cartridge bombs.

  • Said AlMasri

    Al Qaeda's number 3 was <a href="" target="_hplink">killed</a> in an American drone strike May 2012. (Reuters TV)

  • Fazul Abdullah Mohammed

    Mohammed was <a href="" target="_hplink">killed</a> by the Somalian army in June 2011. He led the organization in Eastern Africa. (AP)

  • Abu Musab Al-Zarqawi

    Al Qaeda's leader in Iraq was <a href="" target="_hplink">killed</a> in a U.S. airstrike in 2006. (AP Photo/U.S. Department of State, HO)

  • Khalid Sheikh Mohammed

    Mohammed, the <a href="" target="_hplink">self-described mastermind</a> of the attacks of 9/11, was captured in Pakistan in 2011 and is held at Guantanamo Bay. (AP Photo/FBI)

  • Saif Al Adel

    Al Adel was Bin Laden's former <a href="" target="_hplink">security advisor</a>. He is still on the run. (Getty Images)

  • Adnan El Shukrijumah

    El Shukrijumah is responsible for Al Qaeda's external operations. He <a href="" target="_hplink">lived in the U.S.</a> for more than 15 years. (FBI)

  • Atiyah Abd al-Rahman

    Al-Rahman was Al Qaeda's liaison for Iraq, Iran and Algeria until he <a href="" target="_hplink">was killed</a> on August 22, 2011 in Pakistan. (AP Photo/National Counterterrorism Center)