UPDATE: Elderly woman burned in St-Laurent fire dies in hospital

The Montreal police arson squad is investigating a fire that broke out early New Year's Day in a basement apartment in the Saint-Laurent borough that claimed the life of a 72-year-old woman.

"The principal hypothesis that is being looked at by the investigators, is that a cigarette or something [similar] was used to start the fire," said Montreal police spokesman Daniel Lacoursiere.

The fire began at 3:30 a.m. in the basement of the Keller St. building. 

Flames were brought under control before things spread to nearby buildings.

The woman was rescued from the home having sustained first- and second-degree burns to nearly half of her body. She was in critical condition fighting for her life in hospital, according to Lacoursiere, before succumbing to her injuries the following day.