Montreal: The mother of former Quebec separatist leader Gilles Duceppe died Sunday of hypothermia after being accidentally locked out of her Montreal seniors home during an arctic blast, the coroner said Monday.

Helene Rowley’s tragic death came as extreme winter cold gripped much of eastern Canada, leading Environment Canada to warn of risks of frostbite developing “within minutes on exposed skin” as temperatures plunged to -30 degrees Celsius with the wind chill.

A massive snowstorm also blanketed the region, delaying flights and forcing the cancellation of a snow festival in Montreal — because of too much snow.

Rowley, 93, had ventured out into the storm at 4.15am on Sunday after a fire alarm was triggered and became trapped outside when the building’s back door locked behind her.

Her body was found in the snow just outside the building more than seven hours later. The coroner is investigating.

Authorities told AFP Rowley is believed to not have heard an audio announcement over a loudspeaker that followed the alarm saying that the building was not being evacuated.

Condolences poured in from across the political spectrum over the loss, including from Prime Minister Justin Trudeau and Quebec Premier Francois Legault, who said on Twitter that he and his wife were “shaken by the death of Mrs Rowley.”

Duceppe was a lawmaker from 1990 to 2011, and for 15 of those years lead the separatist Bloc Quebecois party, pressing Quebec issues within the Canadian parliament, including a stint as leader of the official opposition.