Cpl. Phonse Foley said one of the teenagers was driving by the Ville Marie Hotel in Marystown around 1 a.m. Monday when he spotted flames coming from the peak of the building.
Foley said the young man called police and then called his friends who were in the area. Foley said the group, who are all around 18 or 19 years old, then entered the burning building and alerted the guests and hotel staff inside of the fire.
"I guess once he realized that they were the first ones there, they took it upon themselves to make sure that everybody was safe and that everybody was out," said Foley.
"It's certainly our belief that these young men played a crucial role in ensuring that everybody was out and that lives were saved."
Foley said the group was not racing through flames, as the fire had not spread from the top of the building yet. But he said they would have encountered a lot of smoke.
He said if it wasn't for them, those four people may not have survived.
"One person in particular, he certainly owes his life to those young men," said Foley, adding that there were no injuries besides smoke inhalation.
Police said the small hotel with roughly two dozen rooms was destroyed by the blaze and the cause is under investigation.