The blast happened at around 7 p.m. in the home on Sunny Valley Road near Sunny Valley Lane.
A man trying to help the homeowner repair a propane leak was killed when the house exploded, leaving only the chimney standing. The victim was identified as Anthony Fratino, Jr.
The homeowner, identified as 46-year-old John Wilkinson, and a 9-year-old child of the man who was killed were also injured in the blast, which leveled the two-story, Cape-style farmhouse.
Wilkinson and the child, Nicholas Fratino, suffered lacerations and burns and were taken to area hospitals.
Authorities say Wilkinson smelled gas and got his wife and two children out of the house before calling Fratino for help.
Police said onlookers were being kept away because asbestos particles might have blown into the air. Residents reported feeling the blast from miles away.
"The house shook and we thought we were being bombed," a neighbor said. "It was very frightening, and we ran out and saw smoke, but didn't know where the explosion was coming from."
The investigation continues.
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