For the second time in two weeks, a young boy has died at the Mont St. Sauveur Water Park.

Late Monday morning, a 14-year-old boy collapsed as he climbed the stairs to access the "Colorado", a whitewater rafting ride.

The exact cause of death is not yet clear, but it appears a cardiac problem may have led to the teen's collapse.

"That's the main hypothesis at this point, but we won't be able to confirm that until an autopsy is performed," said CTV Montreal's Rob Lurie, reporting live from the water park.

Lifeguards tried unsuccessfully to revive the boy. He was transported to the St. Jerome Hospital, where he was pronounced dead.

"Now was this heat stroke? Possibly. That's one of the things that they will be looking into, but police say there may have been an underlying heart condition at play," said Lurie.

Christian Dufour, a spokesperson for the water park, said the climb up the mountain to access the ride is an intense one -- but there have never been any serious problems.

"It's very rare to see a young child faint like that and of course we're very devastated by his situation."

Nine-year-old drowned two weeks ago

On June 23, nine-year-old Jeremy Mulumba drowned in the park's wave pool, while on a field trip to celebrate the end of school.

About 300 people were in the pool, and three lifeguards were on duty, when Mulumba was found unconscious under eight feet of water.

His death was the first drowning at the water park.

The Surete du Quebec and a coroner are still investigating his drowning.