Fire crews responding to a home in the 100 block of Madison Avenue in Prospect Park just after midnight were advised of possible entrapment inside the home, officials said.
Firefighters were able to quickly extinguish the flames shortly after arrival.
A woman found on the first floor of the home was pronounced dead at the scene, according to Prospect Park Fire Company and CBS3.
A dog also died in the fire, authorities told CBS3.
The cause of the fire remains under investigation.
The incident is being investigated by the Prospect Park Police Department, the Delaware County Criminal Investigation Division, and the Pennsylvania State Police.
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