The attack by the two Canadians -- identified to CBC as Xristos Katsiroubas and Ali Medlej -- and other al-Qaida followers left dozens of refinery workers dead.
Sources told it was likely that Katsiroubas and Medlej deliberately blew themselves up in the blast, CBC reported Tuesday. One of them could be identified only through DNA testing.
The Canadian government at first denied that any evidence indicated Canadians had been involved in the attack, and still work to keep the pair's identities secret.
Sources have told CBC, however, Katsiroubas and Medlej may have traveled overseas with others. Still unclear, though, is whether the others are alive, or whether they were involved in the Algerian gas plant attack.
Katsiroubas and Medlej both were from a middle-class London, Ontario, neighborhood and were thought to be less than 24 years old.
A former friend says that Katsiroubas converted to Islam when he was a teen, CBC said.
Another school acquaintance who talked Katsiroubas in 2009 said, "[It] was really hard to relate to him at that point. He wasn't the same. He had other interests -- kept saying 'let's go to the mosque.'"
"It wasn't that he wanted to take me there," the acquaintance told CBC. "It was that he wanted to go there and he thought a couple of hours spent with me [catching up] was probably a waste of time."
Nearly 40 foreign hostages and 29 kidnappers were killed in the mid-January assault, along with an unspecified number of Algerians.
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