"For a moment my heart froze," Adlan Taramov told CBC News on Friday afternoon.
"I saw that someone who was related to Chechnya would do such a horrible thing. It was very difficult to learn that," he said.
For Eugenia Protsko the important thing is to not tar an entire community.
"They are two individuals and they don't represent the whole nation," she said.
Toronto is home to about 300 Chechens.
Earlier on Friday reporters flocked to an apartment in Etobicoke after discovering that the aunt of the two suspects lived in the city.
And Maret Tsarnaeva wasted no time telling them that she couldn't "believe our boys would do that."
"We're talking about three dead people, 100-something injured, and I do not believe, I just do not believe our boys would do that ... I don't know them in the way that they could be capable of this," Tsarnaeva said.
Dzhokhar Tsnarnaev captured, detained
A manhunt was underway Friday in Boston for 19-year-old Dzhokhar Tsarnaev. Police captured him Friday evening in the Watertown suburb after a homeowner contacted police after seeing blood on a boat in his backyard.
Dzhokhar's brother 26-year-old Tamerlan was killed overnight in a shootout with police, officials said.
- Family of accused bombers divided over allegations
Tamerlan wasn't a devout practicing Muslim, "but just recently, maybe two years ago, he started praying five times a day," she said.
"He has a wife in Boston and from a Christian family, so you can't tie it to religion," she said.
Influenced by radical propaganda
But Taramov, who is studying the radicalization of the Chechen diaspora at the University of Toronto, says the young men may have been influenced by jihadist propaganda on the internet.
"Propaganda of radical ideology going on through the internet that try to brainwash young people that feel isolated, that feel frustrated since they live in a different country," said Taramov.
"When young people feel frustrated — and feel they have a life crisis ... they get influenced by exterior factors such as radical propaganda. They fall victims to these situations."
"I studied radicalization, I know there is propaganda going on, trying to capitalize on youth that feels frustrated and isolated in western communities. This is not just the U.S. Similar frustration can be felt anywhere across the world," said Taramov.
Security expert John Thompson agreed. He said Friday that jihadist groups are recruiting abroad.
"The parents might have left an Islamic society and are not interested at all in radical Islam — but there's someone working on the kids and saying, 'Here's what your identity's really about.' And before you know it they've got a bomb vest strapped on and they're going out to kill someone."