Montreal police believe a drug overdose is the cause of death for two men found in a car underneath the Jacques Cartier Bridge.

Two men, apparently in their fifties, were found lifeless in a car parked at a gas station at the intersection of De Lorimier Ave. and Maisonneuve Blvd. on Friday morning.

When first responders arrived, it was already too late.

“They were probably dead for a couple of hours already. At this moment we did find inside the vehicle some objects that were used to take drugs,” said Montreal police spokesperson Raphael Bergeron.

Police said there are no signs of violence, leading them to suspect the pair died of a drug overdose.

Authorities say, however, it will take a few more days before they can determine what these two men might have consumed before overdosing.

Last week seven people suffered fentanyl overdoses in the Hochelaga-Maisonneuve neighbourhood, which led police to arrest alleged five drug dealers.

Fentanyl is an inexpensive opioid considerably more powerful than heroin.

“Police seized a small quantity of drugs tainted with fentanyl, but it's obvious there's some remaining on the streets,” said homeless advocate Alexandre Paradis of SOS Itinerance.

Most outreach workers now carry Naloxone with them, the antidote to revive people overdosing.

They say users need to be warned that they're in danger, though, because fentanyl is often mixed with other drugs without their knowledge.

“They do cocaine or ecstasy or speed, anything that is illegal, and they (could) have fentanyl in their drug,” said Jessica Turmel of intervention group GRIP Montreal.

In Vancouver, fentanyl is now killing more than one person a day on average.