Four men are recovering in hospital after they were found inside a shipping container at the Port of Montreal Thursday morning.

The men, who are in their 30s or 40s, were all taken to hospital suffering from dehydration and heat stroke, Urgences-Santé operations chief François Labelle said.

They are in stable condition and are expected to recover.

The container arrived onboard the Hong Kong-flagged ship OOCL Montreal. The Port of Montreal's online log shows the ship's last port of call before Montreal was Hamburg, Germany.

A Toronto spokesperson for the Orient Overseas Container Line said an internal investigation is underway.

CBSA now investigating

The police investigation has now been turned over to the Canada Border Services Agency (CBSA).

"The CBSA confirms clandestine passengers were found this morning in a container at the Port of Montreal," CBSA spokesperson Jacqueline Roby wrote in an email to Radio-Canada, CBC's French language service.

Roby said she couldn't provide more information because "the event is ongoing and for privacy reasons."

Andrei Medvedev, a truck driver who was going to pick a different container at the port, saw the slew of emergency vehicles, including paramedics and border police.

"I was kind of curious, kept looking and saw they were parked next to one of the 40-foot containers," he said. "I saw paramedics coming out of this container with a stretcher with [someone on it]."​