Rouleau, 25, was fatally shot after hitting the two soldiers in a parking lot of a commercial plaza in St-Jean-sur-Richelieu, a city about 40 kilometres southeast of Montreal.
Rouleau was one of 90 people being monitored by the RCMP as part of 63 current national security investigations, the RCMP confirmed to CBC News Monday night. RCMP Commissioner Bob Paulson reported the investigations to MPs on the House public safety committee earlier this month.
"We have about 63 active national security investigations on 90 individuals who are related to the travelling group, both people who intend to go [abroad] or people who have returned and have been referred to us by the service," Paulson said on Oct. 8.
Those numbers refer to people suspected of being involved with terrorism-related activities, including financing, not specifically to fighting alongside extremists.
An SQ spokesman, asked whether the police needed the help of the RCMP, said they would address that later Tuesday.
The RCMP are handling the investigation into suspect and his motivations, the SQ said.
On Monday, the RCMP said Rouleau was "known to federal authorities" and that the integrated national security investigations team in Montreal, along with other authorities, worried "he had become radicalized."
The Prime Minister’s Office issued a new statement Tuesday, reiterating that federal authorities had confirmed certain elements clearly indicated Rouleau had become radicalized. Canadians should remain vigilant, the statement read.
Public Safety Minister Steven Blaney, speaking in Saint-Jean-sur-Richelieu Tuesday, said the RCMP are co-operating with the Sûreté de Québec, and federal law enforcement agencies are "monitoring the situation."
"This is a terrible act of violence against our country, against our military and against our values," Blaney said.
What took place, he said, "is clearly linked to terrorist ideology."