Most young Canadian ISIS recruits are being targeted online and are often "social misfits" who sometimes come from troubled families, Defence Minister Jason Kenney says.

Kenney made the comments on CTV's Question Period, days after the RCMP announced that it had arrested, and later released, 10 Montreal teens suspected of wanting to joining the Islamic State group in the Middle East.

Investigators made the arrests after they were tipped off by a concerned parent. Though the teens were released after questioning, their passports were confiscated.

Kenney said most of the ISIS recruitment efforts of young Canadians is happening on the Internet.

"Very typically it happens online," said Kenney. "These are what, in other times, you might have called social misfits, kids that often don't fit in. And sometimes, but not always, they come from families where there have been problems."

According to Kenney, ISIS gives young recruits "some purpose," a phenomenon he says he finds hard to explain or understand.

The minister also defended the RCMP and Canadian Security Intelligence Service (CSIS) response to the interception of the 10 youths at Montreal's Trudeau Airport on May 15.

He said the arrests reinforce the strong relationship between the RCMP, CSIS and communities affected by homegrown terrorism.

The government says some 150 Canadians have travelled abroad to join ISIS. Kenney refused to say how many of those recruits have returned to Canada, citing security concerns, but ensured Canadians that the RCMP and CSIS are working hard to track them.

"It's impossible in a country of 36 million that is an open democracy to track everyone who might potentially become radicalized," said Kenney. "The intelligence agencies do their utmost to track and identify these people if and when they come home, but doing that is a very expensive, labour-intensive process as you can imagine.”

The government recently announced in its budget that it will provide an additional $300 million to Canada's intelligence and law enforcement agencies, including the RCMP, CSIS and the Canada Border Services Agency (CBSA), for counter-terrorism efforts over five years.

ISIS advances reinforce Canadian mission: Kenney

Last week, ISIS overran two cities in the Middle East – the historic Syrian city of Palmyra, home to a UNESCO World Heritage Site, and the Iraq city of Ramadi. Kenney said these kinds of setbacks should be expected in the fight against the terror group.

"We've been clear that no military campaign runs in a simple straight line. There are obviously going to be periodic setbacks and the Iraqi security forces clearly have suffered such as a setback in and around Ramadi, which is regrettable," said Kenney.

For Kenney, the fall of Ramadi reinforces the need for the U.S.-led coalition against ISIS, of which Canada is a part.

"This is an argument for us to continue our military operation," said Kenney. "If Canada and the allied countries were not assisting Iraqi security forces with air strikes and training, the situation would be dramatically worse."

Canada is currently assisting with an anti-ISIS airstrike campaign in Syria and Iraq, and has 69 special forces soldiers training Kurdish Peshmerga in northern Iraq. The mission is set to expire in March 2016.

Kenney said that while the taking of Ramadi was a "wakeup call" for the Iraqi army, Canada's work with the Kurds in the north has been successful.

"The Kurdish Peshmerga, with whom we have been working, have been effective up in their part of the country. The Iraqi army in southern and central Iraq, somewhat less so."

No relations with Iran anytime soon

Iranian-backed Shiite militias mobilized last week to attempt to take back Ramadi. Iran, like Canada, is fighting back against ISIS.

But when asked whether Canada would consider re-establishing diplomatic relations with the Islamic Republic, Kenney did not entertain the idea. Rather, he indicated that Canada will tolerate Iran's fight against ISIS, but not engage with the country further.

"This is a broad coalition. We're not going to agree with everyone who is participating in this all of the time, but we do have a common enemy," said Kenney.

Canada cut off all diplomatic relations with Iran in September 2012, citing its failure to comply with United Nations resolutions on its nuclear programs, its threats against Israel and support for Syria.