The Quebec woman, who agreed to speak to CBC News on condition she remain anonymous for her own safety, said she wants to warn other parents about the risks awaiting young Muslims like her son.
She said after her son converted to Islam, he was recruited online by a radical Islamist group.
'An easy target'
The woman said her son was by nature a pacifist but was perhaps an easy target.
"They played on his generous nature," she says, adding she watched her son change gradually after he converted.
"He stopped listening to music because it was a sin," she says. "He started to cut off contact with girls, then later, with boys who didn't share his vision."
She said he became more and more critical of Canadian society, saying, "Canadian laws are not good. It's Sharia law that should be applied."
"He is convinced that jihad is a part of the religion," she said, adding he told his parents he wanted them both to "burn in hell" if they did not convert as well.
On the no-fly list
The young man has left Canada for Syria, and his mother is aware that CSIS agents suspect him of involvement in radical Islamist activities.
She said his name is on the no-fly list maintained by the U.S. government's terrorist screening centre.
"CSIS knows of some 50 or so young people who have left Canada to join one of these groups," said Michel Juneau-Katsuya, a former CSIS agent who is now president of Northgate — a private security consulting firm.
Social media play a growing role in reaching out to vulnerable young people and radicalizing them, Juneau-Katsuya said.
"Social media are a means of privileged communication between young people, which excludes their family and isolates them with others who sympathize with their cause and think in a similar fashion," he said. "It's also a way of communicating in code."
He said it's a challenge for authorities to keep on top of what's being discussed or to restrict access to radical content.
'Radical discourse' on the increase
Shaykh Omar Koné, a Sufi cleric who leads the congregation at Montreal's al-Iman mosque, said he sees more and more young people participating in this radical discourse.
He said clerics try to guide them in a different direction, but it doesn't always work.
Koné said parents of young Muslims must be vigilant and must not turn a blind eye to radical ideologues who might be trying to influence their children.