In a year-end interview, the prime minister tells the news network TVA that although Michael Zehaf Bibeau and Martin Couture-Rouleau were each alone at the time of their attacks, they might not have been "lone wolves."
"It's true that it was only a single attacker, but it's not necessarily the case that it's only one guy," Harper told host Pierre Bruneau.
"It's possible that there were other people who were around these men. And there's been an arrest in Montreal, as we've already announced."
Harper was referring to the recent arrest of a 15-year-old boy who had allegedly robbed a convenience store in order to participate in terrorist activities. The youth had allegedly been in contact with Couture-Rouleau through Facebook.
"Investigations continue," Harper said.
The RCMP have yet to release a video that Zehaf Bibeau created before the attack.
Couture-Rouleau fatally struck Warrant Officer Patrice Vincent with his car on Oct. 20, also injuring another soldier in St-Jean-sur-Richelieu, Que.
Two days later, Zehaf Bibeau killed Cpl. Nathan Cirillo at the National War Memorial before storming Parliament Hill, where he died in a gunfight.
Harper and his MPs, gathered for their weekly caucus meeting that Wednesday, listened as the gunfire echoed through the marble and limestone hallway just outside the door.
"You're in the caucus room there, all you hear is a whole lot of shooting coming towards you. And you don't know whether that’s a firefight or whether that's just a bunch of guys with automatic weapons wiping everybody out in their path," Harper told the CBC's Peter Mansbridge in an interview.
Multiple MPs told The Canadian Press that while a small group of Conservatives fled in the first few minutes, Harper wound up in a closet adjacent to the doorway — unbeknownst to many in the same room who thought he had also left.
At the time the attack began, there were no Mounties in the caucus room with Harper, only unarmed Parliament Hill guards — something RCMP Commissioner Bob Paulson afterward said would be addressed.
MPs barricaded the doorways, and had to be convinced to eventually open a door to the RCMP, who then whisked Harper away, according to some in the room.
Senate Speaker Pierre-Claude Nolin recently told reporters that he had never seen the prime minister look so pale as that day.
In the interview Mansbridge, Harper said he would not comment on being put in the closet. He also suggested he was not as scared as some might have been, because he has received training from the RCMP.
"Well the RCMP has run me through some drills to simulate these kinds of situations. So as you know, as a prime minister, you're in a little bit different position of other people," Harper told Mansbridge.
"As prime minister I have access obviously to all the government’s intelligence, all the security risks that are faced by the country and by me personally. So, you're in a different head space than most other people who are suddenly facing this kind of situation for the first time."
Who was the first person Harper called when he had the opportunity that day?
"I called my mom just to assure her I was OK and...I could tell by her voice that she was concerned," he said.
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