PITTSBURGH (KDKA/AP) – Authorities in western Pennsylvania say flammable items that were too close to a space heater could have started an early morning fire that killed a woman.

Pittsburgh public safety officials cited the possible cause Monday in the blaze that killed 73-year-old Rose Pressley on Friday.

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Authorities said police initially responded to a 1:40 a.m. Friday call to 911 and found smoke coming from the basement of the East Hills home. The blaze spread, causing the first floor to collapse.

The medical examiner’s office said Pressley died of thermal and inhalation injuries in the blaze early Friday. Her death was ruled accidental.

Firefighters found Pressley dead on the second floor of the home. Friday was also her birthday.

Crews initially looked for her husband, but it was later determined that he had previously been admitted to a local hospital for an unrelated issue.

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The house suffered severe damage and the first floor collapsed. A firefighter fell through the floor as the first floor collapsed, but he was able to get out and resumed fighting the blaze.

Firefighters were evacuated from the building when the flames started to spark back up.

The fire happened almost 20 years to the day that three Pittsburgh firefighters died while battling a fire on the same street.

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