Three young men were struck and killed by a Via Rail train early Sunday, in an area of southwest Montreal police say may have made it hard to hear the locomotive coming.

The three were among a group of five teenagers, their ages ranging from 17 to 19, who were in an abandoned area under the city's busy Turcot Interchange. Police say the freeway's large concrete support pillars may have made it difficult to hear the approaching train.

"The big concrete structure made ... it difficult for them to understand that there's a train that was coming on," Montreal police Const. Danny Richer told The Canadian Press.

"That's why maybe they didn't understand and see that the train was coming."

The train was just 10 kilometres from Montreal's Central station when it struck the youths. Two of the men were pronounced dead at the scene, while the third succumbed to his injuries in hospital.

The two survivors were also taken to hospital. None of the victims have been identified.

"Investigators are still on the scene trying to know what happened," Richer said Sunday, suggesting the teens may have been spraying graffiti in the area before they were struck.

The train was travelling at a speed of about 10 kilometres per hour when the incident occurred. None of the 45 passengers aboard the train were injured.

The train had been scheduled to arrive in Montreal three hours earlier, but Via Rail spokesperson Elizabeth Huart said its departure was delayed by an unrelated accident GO train accident that killed a pedestrian in the Toronto-area.

"This is a tragic accident and a sad reminder that nobody should ever trespass on railway property. It is extremely dangerous and it is against the law," CN spokesperson Julie Senegal said.

With files from CTV's Genevieve Beauchemin in Montreal and The Canadian Press