"We all have a responsibility and our studies clearly demonstrate that in 80 per cent of the [cases], when an individual is willing to travel for a terrorist purpose, the people around are aware or informed of that situation," Blaney said outside the House of Commons.
"It is important to report it to the authorities for the well-being of that individual, for not being further radicalized and also saving human lives."
CBC News reported Wednesday on a woman in Edmonton who recruited a Canadian woman to join ISIS. On Thursday, media reports said six Quebeckers had travelled to Turkey and are believed to be on their way to Syria to join jihadists there.
Blaney said Wednesday that Canada "cannot become an exporter of terrorism" by letting Canadians travel to join ISIS.
"This is not the Canadian way of living. And even added to that, if a terrorist traveller is coming back, it's even a bigger threat to our security. So that's why we need to prevent Canadians from travelling for terrorist purposes," he said.
MP: current powers sufficient
Blaney urged MPs to move faster on Bill C-51, his proposed anti-terrorism legislation, which would vastly expand the powers of the Canadian Security Intelligence Service (CSIS). One power would be the ability to disrupt suspected terrorist activities, with very few limits.
New Democrat public safety critic Randall Garrison questioned the need for some of the powers proposed in the bill, arguing that Canada's security and law enforcement agencies already have the power to stop Canadians from leaving to join terrorist activities.
Currently, CSIS can work with police forces to stop someone from leaving the country if they suspect that person is leaving to participate in terrorist activities.
"Very clearly it's illegal to leave Canada to join terrorist activities abroad. So there is power, existing power, that the RCMP could use to stop people leaving to join terrorist activities abroad. So when the government says it's not there, it's simply not true," Garrison said Thursday at the public safety committee.
"When they say CSIS can't contact the families, the story [the Conservatives] cite ... actually disproves their point, because CSIS did talk with the family. So we believe, and we would like to hear experts to confirm, that the powers that they're talking about already exist in current legislation."
Working with communities vital
Garrison said he didn't know why officials didn't stop the Canadians who left to join jihadists.
"Is it a question of resources? I don't know. I'd like to have witnesses before committee so we can explore those questions," he said.
Christian Leuprecht, a counterterrorism expert at Royal Military College and Queen's University, told CBC News Network that Canada needs to focus on the conditions that make it more or less likely someone will leave, both through prevention and disruption.
An important element in preventing radicalization is for someone to feel part of a country's social fabric, he said, and working with communities can also help when those communities have concerns.
"This is why both CSIS and the RCMP, and the countering violence extremist programs and strategy, are very much looking to reach out to communities, to make sure that they work closely with communities, not in terms of gathering intelligence, but making sure that communities feel comfortable talking to them when they feel that they might have a challenge within their midst or an individual within their midst," Leuprecht said.