Serial crimes? Quebec police believe there could be more victims after arresting man in 22-year-old killing

Quebec's provincial police force says it has deployed its serial crimes investigations unit after a 47-year-old man was charged with murder in a 22-year-old cold case because investigators believe there could be other potential victims.

On Wednesday, the Sûreté du Québec (SQ) arrested Marc-André Grenon of Granby, Que. in connection with the death of a 19-year-old junior college student, Guylaine Potvin. Her body was found in her apartment in Jonquiere, Que, north of Quebec City, on April 28, 2000.

One day after his arrest, the accused was charged with first-degree murder and aggravated sexual assault in the teen's killing.

Grenon was also charged with the attempted murder and sexual assault of another woman who was violently assaulted and left for dead in Quebec City the same year. That victim’s identity is protected by a publication ban.

Quebec provincial police say they've made an arrest in the homicide of a junior college student 22 years ago. Guylaine Potvin, shown in a Surete du Quebec handout photo, was found dead in her apartment in Jonquière, Que. on April 28, 2000. THE CANADIAN PRESS/HO-Surete du Quebec

On Friday, police said it has mobilized its structure de gestion des enquêtes sur les crimes en série (GECS), since "the investigation tends to show that the suspect could have had other minor or adult victims."

The SQ describes the police unit as a "unified command structure" coordinated by provincial police by pooling resources from other police services "to quickly identify and arrest crimes committed by predators."

As it seeks assistance from the public, police also released a series of photos of Grenon, dating between 1994 and 2019, given his alleged historical crimes.

Marc-Andre Grenon was arrested on Wednesday, Oct. 12, 2022, in the death of 19-year-old Guylaine Potvin, who died in 2000 in Jonquiere, Que. (Source: Surete du Quebec)

Anyone with information about Grenon is asked to send a confidential tip to the SQ's Central Criminal Information Unit at 1-800-659-4264.

Potvin's family was relieved that after 22 years an arrest was finally made in the cold case that spanned two decades.

“We always hoped that this day would come,” said Jeannine Caouette, Potvin’s mother, despite the difficulty she described of re-opening old wounds.

Wednesday was also a significant day for the officers who worked on solving the crime over several years.

“It was an answer that we had been waiting on for a long time,” said Bruno Cormier, one of the original officers assigned to the case, who is now retired.