Roughly one year ago, Mohamud Mohamed Mohamud, then 19 years old and a biology student at Toronto's York University, met a group of friends at a hip-hop dance audition, and later partied and grew close with them. But he eventually cut them off — through the spring and summer of 2014.

By July, while those friends thought they lost touch with an athletic, outgoing man, who at times seemed unsure of himself and his identity, his family in Hamilton was frantically trying to warn the Canadian Security Intelligence Service (CSIS) and RCMP that their eldest son may have taken up arms with Islamic State in Iraq and Syria militants.

Earlier this week, CSIS, albeit unofficially, told the family there were reports he was killed by the anti-ISIS military campaign, apparently dying during attacks from Kurdish forces in northern Syria last week.

His extended family has gone into seclusion to deal with their loss, said Hamilton lawyer Hussein Hamdani, who tried to help the family once they realized he was "crossing over."

What happened that led to the change remains a mystery, he said.

"That is an important question that we must look at and try to find the answer to."

Mohamud Mohamed Mohamud, pictured here, is a 20-year-old Hamilton man beleived to have been killed while fighting for ISIS in northern Syria. (Calamada.com) York University said is not a current student and its policy is to only comment on those who are. The RCMP, as well as the Department of Public Safety and Department Foreign Affairs, all declined to comment on ongoing investigations. CSIS did not return calls Wednesday. MohamudCSIS

The Department of Public Safety said an estimated 130 Canadians have gone to fight for ISIS. Since the U.S. launched airstrikes to combat ISIS, it's believed Mohamud is the first Canadian to die in the recent attacks against the militant group.

Changes noticed by family, friends

Janaan Issaka, a friend of Mohamud's from York University, said he was one of her “closest friends at school last year.”

“I met him around this time, end of September; we auditioned for the hip-hop dance team and that's where I met him,” Issaka said, describing a extremely social man who retreated later in the spring.

“It's so crazy, knowing the kind of person he was and thinking that somebody could be so brainwashed,” Issaka said.

Around the end of the school year, she said, Mohamud said “I don't party anymore, I don't do anything like that, I'm just focusing on my religion.”

Hamdani told CBC Hamilton that the family noticed the same changes — a man who was on a scholarship and who wanted to be a doctor becoming harsher in his views and withdrawing from his communities, including the Muslim community.

"He was seeking his new community online," said Hamdani, which is where his radicalization apparently began.

The family lost track of him during this time as he moved between his family here and his father in Minneapolis. They tried to report him missing at one point. And then the family traced him to Turkey via his cellphone.

Hamdani said he was approached by the family in July, when they realized their son was in Turkey attempting to cross into Syria.

“They reached out to him and asked what was going on, and that's when he said 'my intention is to cross over and go to the Syrian battlefront.'”

Hamdani immediately connected the family with the RCMP and CSIS. But they were too late to stop him.

“The hope and the desire was we'd be able to catch him before he crossed the border from Turkey into Syria. They learned now that once he's off the plane in that end, he's with his handlers and there's an underground railroad," said Hamdani.

“We were just a day or two late. Had we known about this, had the RCMP or CSIS known about this just two days earlier, they could've contacted their connections from the Turkish authorities and stopped Mohamed from getting off the plane.”

Just days ago, a photo circulated of a Canadian-Somali who was killed. That photo is of Mohamud Mohamed Mohamud, confirmed Hamdani.

Hamdani said even if the reports turn out to be wrong, the family is dealing with a loss because Mohamud is "not the son they knew."

Principal said Mohamud was 'really well-liked'

​Susanna Fortino-Bozzo, principal of St. Thomas More Catholic Secondary School in Hamilton, confirmed Mohamud was a student, and called him "vibrant." She said he was "sociable" and "really well-liked," although he did not graduate from St. Thomas More, leaving the school in Grade 11 and later graduating at Sir Allan MacNab Secondary School in Hamilton.

Susanna Fortino-Bozzo, principal of St. Thomas More Catholic Secondary School in Hamilton, said Mohamud Mohamed Mohamud was a well-liked, `vibrant` student when he attended her school. Mohamud left the school in 2011 to attend another nearby school, Sir Allan MacNab Secondary School. (John Rieti/CBC) Mohamud is believed to be the first Canadian reported jihadist killed since anti-ISIS military action, led by airstrikes by U.S. forces last week, have amped up.

But it's believed he's not the first Canadian killed while fighting for ISIS — a Calgary imam says he knows at least five who have died within the last year.

Fortino-Bozzo said she couldn't share details of Mohamud's file due to privacy issues.

"Ultimately, our prayers are with everyone impacted by this tragic death," though she quickly pointed out it may not be true that Mohamud is in fact dead. "His family will be in our prayers."

The picture was originally circulated on a pair of pro-Shabab websites that didn't name Mohamud, but said the person in the photo was killed. A Sept. 15 Voice of America report claims to have spoken with Mohamud's father, who hasn't been named, in Minneapolis who said he was "shocked" to learn his son left the U.S. to overseas in mid-July.

"My son was a student, he suddenly changed," the man told reporter Harun Maruf. "He used to pray but he increased it to 24 hours of prayers, and he was rarely away from mosques. He arranged his travel without my knowledge, and then he ended up in Syria. All of us [in the family] are very saddened. We did not expect he would do this.”

Jason Tamming, press secretary for Steven Blaney, Canada's minister of public safety and emergency preparedness, notes that 130 Canadians have left to fight for ISIS.

"This is a serious problem, and demands a strong response," Tanning said Wednesday.

ISIS path of recruiting long, imam says

Calgary-based imam Syed Soharwardy, founder of the Islamic Supreme Council of Canada (ISCC), said at least five Calgary-based Muslims have been converted to fight for ISIS, a process that starts with converting to Wahabism, a more radical form of Islam.

"The path of recruiting is a very long path. It's not just one month, or one night. It depends on how quickly they get brainwashed. But the process is in universities, in colleges, in some of the mosques, in community centres, People organize lectures and they invite Wahabi (speakers)," Soharwardy said Wednesday.

"Those speakers in fact convert people to Wahabism. And once people accept the Wahabi belief, that which is based upon intolerance towards disagreement, Wahabi belief is basically that they are the only one who will be in heaven and the rest will go to hell regardless if they are Jewish, Christian or Muslim…. Then they bring that person close to them, then slowly they bring that person underground, start brainwashing them, and then getting that person overseas through internet, through social media, through different websites."

With files from John Rieti.

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