The Quebec Provincial Police said Sunday that five people died and about 40 are missing in the derailment and explosion on the weekend of a train carrying petroleum.
The number of dead was raised after two more bodies were found in the ruins of buildings destroyed by the explosion and the fires that broke out after the derailment in the small town of Lac-Megantic, which has about 6,000 residents and is located 250 kilometers (155 miles) east of Montreal.
About 30 buildings in the center of town were completely destroyed.
Relatives and friends of the people who were in town at the time of the accident have created a Web page with an eye toward determining the whereabouts of their loved ones.
Quebec authorities warned that the number of fatalities could rise substantially as rescue and recovery teams gain access to the central blast zone.
More than 24 hours after the accident, which took place about 0500 GMT on Saturday, two cistern railcars continued burning and firefighters said that they could explode, a situation that is making rescue and recovery work more difficult.
For the moment, authorities have not made any statements regarding how the accident could have happened.
The train included five locomotives and 77 cistern cars filled with oil.
The company that owns the train, Montreal Main & Atlantic Railway, said that it was parked without an engineer on the outskirts of the town awaiting a shift change but then - for reasons that are not yet known - it began moving.
A woman who witnessed the accident told local media that the train was already in flames an hour before it derailed in the center of town. EFE