By 2006, Mr. Katsiroubas had left behind his Greek Orthodox upbringing for Islam, praying daily with Mr. Medlej at the high school, one former schoolmate said. Mr. Katsiroubas started going by the name “Mustafa,” sporting a long beard and then, after dropping out of school around Grade 11, donning more traditional Muslim clothing.
“Maybe he just found it difficult, maybe he didn’t have the support,” Mr. Alsaadi said. “Maybe it was the people he hung around with didn’t value school, per se, and wanted to just move on and do other things.”
Indeed, the friend who grew up with Mr. Katsiroubas said “Mustafa” started hanging out with a different crowd, all but ignoring this former friend at school. “Right away, he changed [after converting],” he said. “He travelled many places and came back with a beard. You couldn’t recognize him. He started wearing different clothes. You’d see him in the smoker’s pit and he wouldn’t say a word to anyone.”
The nature of any travel outside Canada is a major question mark in this evolving tale. It may be what prompted CSIS to ask the RCMP to put Mr. Katsiroubas and Mr. Medlej on their radar two years ago, a move that suggested law-enforcement authorities were increasingly concerned about their potential crimes.
When threats are felt to be serious enough, CSIS sends a “disclosure letter” or an “advisory letter” to the RCMP concerning the most dangerous extremists. The disclosure letters provide tips and leads to the Mounties, while advisory letters provide the RCMP with information that is intended to support police searches, wiretaps and, eventually, criminal charges.
Little is publicly known about where Mr. Katsiroubas had journeyed before meeting his death at the Algerian gas plant in January. Mr. Alsaadi said he believes Mr. Katsiroubas and Mr. Medlej left Canada in 2009 – for where, he doesn’t know – but the pair must have returned before venturing to North Africa because they were both spotted in London in the years between.
The friend who went to elementary school with Mr. Katsiroubas said he saw Mustafa in early 2012, shortly after one of Mr. Katsiroubas’ high-school friends, Said Hadbai, was shot dead after he reportedly stepped in to help a friend involved in a fight. The friend said hello and offered his condolences; Mr. Katsiroubas, whom the friend said was “dead to [the family]” by this point, offered but a nod.
Mr. Medlej, for his part, got married sometime in late 2009 or early 2010. A friend posted a message to Facebook on Jan. 9, 2010, saying his “bro Ali Medlej” had just got married. The day before, the friend wrote that Mr. Medlej was planning to “hang” with him and Mustafa in London – that they were going to “the mosque.”
A year later, Mr. Medlej was working at a downtown London Hasty Market.
Mr. Yoon came to the Muslim faith later than Mr. Medlej and Mr. Katsiroubas, converting from Catholicism to Islam three or four years ago, his older brother told The Globe. One woman who said she worked with Mr. Yoon while he was a busboy at a Mandarin restaurant in 2008, and then again when he hauled furniture from the stockroom at a Leon’s warehouse in 2011, noticed a major shift in those years.
At Leon’s, he prayed daily and refused to converse with female supervisors since, he said, women had no business being “superior.” He flooded his former coworker’s Facebook feed with so many quotes from the Koran that she ultimately deleted him from her social network.
“He was this fun-loving guy at the Mandarin,” she said, adding that he used to have after-work drinks with coworkers and spend time with a girlfriend. “And then when I saw him at the Leon’s, it was a complete shock. He isolated himself from people and hung out alone.”
One of Mr. Yoon’s two older brothers, who answered the door Wednesday at his parents’ White Oaks dwelling with tired, red eyes, said Mr. Yoon became a “better person” when he adopted the teachings of the Koran, fostering a better relationship with his family.