Tshiuetin Rail Transportation rail conductor Joe Shecanapish was unable to bring back power to the train, which was heading to Sept-Iles, Que. from Schefferville, Que.
"We did everything we can. We couldn't do it. Water froze, toilets froze, everything," he said.
Shecanapish said they tried to squeeze people into a small cabin to warm up. He said some blankets were provided to passengers.
During the ordeal, temperatures ranged from - 26 C to - 33 C.
The train stopped about 65 kilometres from Labrador City, with about eight hours to go before its final destination. It was hours before the town was notified about the train.
"Minus forty. It's like, hey. Right now my feet are still cold," said Simon Einish, who was travelling with his family to Ontario.
Some of the passengers were taken to the hospital as a precautionary measure, but there were no major injuries.
Fire Chief Joe Power, who was one of the first to the train, said the passengers were lucky the train stopped where it did
"It could have been a lot worse this evening. They could have been 100 km or so up the track with no help."
The passengers were eventually bused to Labrador City, where they spent the night.