Michael Zehaf Bibeau so angered some of the men at the Ottawa Mission because of his complaints about Canada that there was almost a fight in recent days, said Norman LeBlanc, a 60-year-old former truck driver who frequents the shelter.
"He went on for more than an hour about how much this country sucked and how he wanted to get out of here, and he was furious about the passport," LeBlanc said Thursday outside the mission.
"That made a lot of the others guys mad, and they were going to take him out back and give him a beating."
Hours after the shooting Wednesday, police descended upon the mission, removing a hockey bag from Zehaf Bibeau's locker that was so heavy it required two men to haul it outside into an armoured vehicle, LeBlanc added.
Police refused to elaborate on the contents of the bag.
Zehaf Bibeau often prayed with two Somali men in the shelter in an east-facing window in accordance with the Muslim faith, LeBlanc said.
One of them, Abdel Kareem Abubakrr, denied his new friend's actions had anything to do with his faith.
"He was a crackhead, I think," he said.
Despite his recent struggles, however, those who knew Zehaf Bibeau as a younger man say he showed promise only a few years ago.
He attended exclusive, private high schools in the 1990s in Montreal and the nearby city of Laval. Today, tuition at two of the academies ranges from $3,000 to $4,500 per year.
The principal of College Laval said Zehaf Bibeau studied there from 1995 until the middle of the 1998-99 academic year, when his parents removed him without explanation.
The mere fact Zehaf Bibeau studied at College Laval suggests he had a bright future, Michel Baillargeon told The Canadian Press.
"If this young man was with us for a couple of years, that means he had good grades," said Baillargeon, who described Zehaf Bibeau's record as nondescript.
He was also remembered fondly by someone at another local high school he attended. That person paid homage to "Mike" in a blurb published in the Saint-Maxime high school yearbook, according to the Laval Courrier newspaper.
The undated write-up described Zehaf Bibeau as a friendly guy, a new kid who barely had any friends at the school when he first arrived in the middle of Grade 10.
"He didn't know very many people, but in a short time everyone knew him," said the short message authored by the unidentified friend. It was published Thursday by the Laval Courrier.
"Mike is a sociable and intelligent guy. He likes to laugh and his smile makes girls crack up. He will go far in life. He will surely be a business man in the near future.
"Follow your heart. Take care of yourself. I adore you."
A former acquaintance of Zehaf Bibeau's father said he believes the young man's path would eventually take him to Libya.
The ex-owner of a Laval coffee shop where Bulgasem Zehaf was a regular customer said the father told him how he brought his son to live with him in Libya for a while around 10 or 15 years ago. The move, the man added, followed Bulgasem Zehaf's divorce from Bibeau.
The man, who spoke to The Canadian Press on the condition his name not be published for fear of recriminations from the community, said Bulgasem Zehaf used to buy used cars in the Montreal area, fix them up and ship them to Libya, where he sold them.
He remembered how much Bulgasem Zehaf would glow when he talked about his son.
"He loved his son very, very much," said the former cafe owner. "He loved him because he was his only child, I believe."
The man also recalled how the proud father used to call his son Abdallah, not Michael.
At a news conference Thursday in Ottawa, RCMP Commissioner Bob Paulson said Zehaf Bibeau's passport application had not been denied, but was still being processed.
"It was in the process of being evaluated," Paulson said. "He didn't have it, but the investigation into whether he would have it was ongoing."
At the shelter, Abubakrr said Zehaf Bibeau told the men that he had left Vancouver for Ottawa in an attempt to obtain a passport. The Somali man said his new prayer-mate wanted to leave Canada to get treatment for his addiction because he didn't feel he could get help in Canada.
Three days ago, Abubakkr said, Zehaf Bibeau began taking drugs again and started espousing "extremist ideas" — Abubakkr wouldn't elaborate — because he was frustrated about his failure to obtain a passport.
"He was a good guy, he was talkative, a very lovely person, but he was a drug addict," Abubakrr said. "In the last three days, he shifted."
Zehaf Bibeau had a criminal record for petty crimes in both B.C. and Quebec. He visited a mosque in Burnaby, east of Vancouver, for several months in 2011 until he was told not to return, said Aasim Rashid of the B.C. Muslim Association.
"He did float in and out of the mosque," said Rashid.
"He's described as somebody who didn't have a very stable life. He was moving in and out of places, in and out of cities, and he was looking for a job. He was described as someone who was a little rough around the edges."
Rashid said Zehaf Bibeau approached administrators to complain that the mosque was too liberal.
"He had some objections against the mosque administration for their openness and their being so inclusive," he said.
"So they sat him down and explained to him that this is how the mosque runs, and they didn't really hear anything of that nature again."
Zehaf Bibeau's mother, Susan Bibeau, released a statement on Thursday apologizing for her son's actions.
"I am mad at our son; I don't understand and part of me wants to hate him at this time," the statement said.
"(He) was lost and did not fit in. I, his mother, spoke with him last week over lunch; I had not seen him for over five years before that. So I have very little insight to offer."
Another man at the mission, Tom Wilson, said Zehaf Bibeau slept in the bunk beneath him on his first night at the Ottawa shelter after they checked in together two weeks ago.
"He had this big hockey bag that he put down on the ground and it sounded like it was really heavy so I asked him, just as a joke: 'What, have you got a body in there? What the hell is in there?'" said Wilson.
"This past Sunday, I saw him down in the lobby all irritated about something, saying: 'I gotta get out of here.'"
A man at a Vancouver shelter, who would only be identified by his first name, Steve, said he knew Zehaf Bibeau as a man who wanted to go to Libya, his father's birthplace, and spent money on crack and heroin.
"He had some problem with his passport and he wanted to get that sorted out so he could go to Libya," Steve said. "He hitchhiked from here some time in September to get to Ottawa."
— With files from James Keller in Vancouver
Follow Lee-Anne Goodman on Twitter @leeanne25
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