Guillaume Gelinas, 22, the son of one of the two people killed in Terrebonne Thursday, has been arrested on two counts of premeditated murder.

The bodies of Luc Gelinas, 54, and Julie Lemieux, 35, were discovered Thursday morning at their home north of Montreal. They had reportedly been stabbed to death.

Police spent much of Thursday looking for Gelinas's son Guillaume, a soldier who had been living with his father and stepmother since his return from Afghanistan.

The suspect is the son of Luc Gelinas, who was in a relationship with Julie Lemieux for the last eight years.

If one were to judge by undated photos posted on social media, the couple had a good relationship with Guillaume Gelinas and indeed he even posted birthday wishes to his father's Facebook page on the day the bodies were discovered in their home on Pierre Le Gardeur Blvd in the Lachenaie sector of Terrebonne. 

Police found Guillaume Gelinas - a former military reservist who served in Afghanistan for eight months between 2010 and 2011 - in Gatineau and questioned him at length.

Late Friday afternoon police announced that Gelinas would be arraigned on the charges in a court apperance in Joliette Monday.

The two victims were executives with the SAQ, Quebec's alcohol authority. Gelinas was the vice-president in charge of real estate and engineering at the Crown corporation, while Lemieux was an accounts executive.

A statement from the organization said employees were in shock over the brutal deaths. It offered its condolences to the families and relatives and offered support to their colleagues.

"Luc Gelinas and Julie Lemieux, two longtime employees, were recognized for their enthusiasm, commitment and kindness," the statement said.

Crime-scene technicians and detectives spent much of Thursday night and early Friday morning gathering evidence at the home, which borders on farmland.

Autopsies were performed on the bodies.

-With a file from The Canadian Press