ST. PAUL, Minn. (WCCO) — Authorities say a married couple that died in a house fire last week died as a result of smoke inhalation.

Crews responded to the scene at about 4:30 a.m. on March 13 after a driver going by noticed flames coming out of their home near Smith Avenue South and Morton Street West.

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The victims were Peter and Maureen Michalek, ages 71 and 66, respectively.

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The couple’s niece, Heather Clemen, said a large abdominal tumor kept her aunt Maureen mostly confined to bed with IVs. She said her uncle Pete took care of his wife around the clock to keep her out of a nursing home.

Authorities said the fire began in the bedroom, and was likely caused by a burning cigarette.

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Maureen Michalek was found in her bedroom, and Peter Michalek was found on the floor of his bedroom on the second floor.