A 64-year-old woman died Tuesday after a fire at a home in Montreal's Pierrefonds neighbourhood, police confirmed.

The fire broke out inside a unit in a sixplex near the corner of Elgin and Orchard streets around 9:30 a.m.

When firefirefighters arrived on scene, smoke could be seen coming from the windows of the residence.

The woman was taken into the care of first responders for smoke inhalation and sent to hospital in critical condition, said a spokesperson for the Service de sécurité incendie de Montréal (SIM).

Véronique Dubuc, a police spokesperson, said the woman was later pronounced dead in hospital.

Two families were assisted by the Red Cross. 

The cause of the fire is unknown. The Montreal police arson squad is leading the investigation into the fatal fire.