MONTREAL -- One person has died and several others were hospitalized following a large, five-alarm residential fire in Montreal's Southwest borough Sunday. 

About 150 firefighters descended on the blaze at Les Habitations Angers, a building that provides low-cost housing for many seniors at Angers Street and Galt Street.

Seven people were brought to hospital because of smoke inhalation, and one for cardiac arrest, who later died.

Authorities believe the fire started on the sixth floor after a cooking device was left on. 

Earlier on Sunday, firefighters wrote to social media that they were responding to a one-alarm fire, meaning the risk was relatively low, at 9:08 a.m. Sunday.

By 9:15 a.m., the fire had reached the five-alarm catagory, which typically requires heavy firefighter presence. 

Fire

Smoke emerges from a window at the Les Habitations Angers in the Southwest borough on April 11, 2021. (Iman Kassam, CTV News) 

"It's elderly people that live at the premises," a spokesperson for the Montreal firefighters told CTV News as the event was taking place. "So it will take longer for them to evacuate." 

Many of the residents are elderly or people with low-mobility.

All residents were evacuated and taken into Red Cross facilities. Authorities say the damage to the building is too great to allow residents back inside.

"The smoke is terrible, smells like burning plastic," one witness wrote on social media.

Videos posted online show plumes of smoke escaping from windows on the sixth and seventh floor of the building, where the fire is most intense.

Shortly after noon, firefighters wrote on social media that the situation was under control.

-- With reporting from CTV News Assignment Editor Max Harrold.