The Philadelphia Fire Department announced the official cause of the fire that killed two young boys and injured seven other people in the Olney section of Philadelphia.
The Department says that an electrical heater attached to an extension chord broke down, causing an electrical fire inside the house.
There were also reportedly no fire alarms inside the home.
The fire occurred Tuesday, Feb. 22 on the 100 block of Sparks Street.
Two boys under the age of 12 died during the blaze.
The injured included four other children under 12 years old, two adult males under 30 and an adult woman under 30.
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