A woman about 84 years old died Sunday night in a South Philadelphia house fire, police said.

Firefighters extinguished the blaze at a private home on the 1400 block of South Clarion Street at about 9:41 p.m. and found the woman in the second-floor front room, police said. She was taken to Thomas Jefferson University Hospital, where she was pronounced dead at 10:25 p.m.

The cause of the fire was not immediately known, police said. The Fire Marshal’s Office was investigating.