A woman in her fifties is in critical condition following a fire at 4437 St. Jacques in St. Henri. 

Firefighters rushed to the building, near the corner of Lacasse, at around 6 p.m. Thursday and extinguished the blaze, but not before the woman suffered serious injury.

The cause of the fire remains unknown but police believe that it might have resulted from an accident.

Fire investigators are studying the possible causes.