This story originally appeared on 6abc.
Authorities in Atlantic County said Tuesday that they have determined the cause of a house fire and explosion that killed four people earlier this month.
Investigators said the August 3 fire was sparked by an enormous amount of explosives found on the first floor of the home in Buena.
Police said hundreds of pounds of chemicals and materials used to make commercial-grade fireworks were found in and around the home, as well as in a vehicle parked outside.
Gas utilities have been ruled out as being an attributing factor, investigators said.
In July, authorities said they found evidence of the possession of fireworks in this area, but no criminal charges were filed.
A 1-year-old girl and a 16-year-old girl were among those injured in the explosion. Both victims were flown to St. Christopher’s Hospital for Children in Philadelphia.
Authorities say a 2-year-old boy, a 3-year-old girl, and two men ages 52 and 73 died in the explosion.
The identities of the bodies found have not been released.
Video from Chopper 6 immediately after the explosion showed the home had been reduced to rubble and debris could also be seen around the yard.
Neighbors said the explosion was so large that car alarms in the area started going off.
Federal and local partners assisted with the investigation.
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