MONTREAL – Montreal police are investigating after firefighters stumbled across a marijuana grow operation while responding to a fire in LaSalle.

The blaze happened at 10:10 p.m. Monday on Lafleur Avenue.

“There was marijuana found inside the house and there were three people treated for smoke inhalation,” said Montreal police spokesperson Manuel Couture.

Their lives are not in danger, he adds.

The Montreal police arson squad is onsite to determine the cause of the fire.