FILE - Emergency personnel search the debris, Thursday, Aug. 11, 2022, in Evansville, Ind., as authorities work to determine the cause of a house explosion that killed three people and left another person hospitalized. Officials say an August house explosion that killed three people has been ruled “accidental” after investigators traced the blast to a leaking natural gas line in the home’s basement. The Indiana State Fire Marshal said Wednesday, Nov. 2, its joint investigation with the Evansville Fire Department into the Aug. 10 explosion determined the leaking gas line “was found uncapped, with the valve in the open position.” (MaCabe Brown/Evansville Courier & Press via AP, File)
FILE – Emergency personnel search the debris, Thursday, Aug. 11, 2022, in Evansville, Ind., as authorities work to determine the cause of a house explosion that killed three people and left another person hospitalized. Officials say an August house explosion that killed three people has been ruled “accidental” after investigators traced the blast to a leaking natural gas line in the home’s basement. The Indiana State Fire Marshal said Wednesday, Nov. 2, its joint investigation with the Evansville Fire Department into the Aug. 10 explosion determined the leaking gas line “was found uncapped, with the valve in the open position.” (MaCabe Brown/Evansville Courier & Press via AP, File)

EVANSVILLE, Ind. (AP) — An August house explosion that killed three people in a southern Indiana neighborhood has been ruled accidental after investigators traced the blast to a leaking natural gas line in the home’s basement, officials said Wednesday.

The Indiana State Fire Marshal said its joint investigation with the Evansville Fire Department into the Aug. 10 explosion determined the leaking gas line “was found uncapped, with the valve in the open position.”

Gas line meter data “showed a sharp increase in gas usage beginning two days before the blast,” the State Fire Marshal said in a news release. “No additional evidence was found to determine how the valve was opened; however, there is no indication of foul play.”

Investigators said testing found that the gas lines between the home’s meter and the mainlines of the local utility, CenterPoint Energy, were in “proper working order.” Testing also confirmed that the odorant additive Mercaptan was present in the gas line leading into the home.

“It could not be determined how the occupants were unaware of the gas accumulating in the home,” the news release states.

The cause of the deadly explosion was ruled accidental. Although investigators could not conclusively identify the ignition source that ultimately ignited the gas, they found that “electrical devices and other appliances in the home could have served as an ignition source.”

CenterPoint Energy said in a statement the State Fire Marshal’s report “further supports the company’s findings, determining that an accident inside the house, independent of CenterPoint Energy’s system, was the cause of the incident.”

The explosion, which was captured on video, launched wooden boards, window glass, insulation and other debris at least 100 feet into the air in Evansville, the Evansville Courier & Press reported.

Authorities said the explosion damaged 39 homes, leaving 11 of them uninhabitable in the Ohio River city about 170 miles southwest of Indianapolis.

A married couple, 43-year-old Charles Hite and 37-year-old Martina Hite, were killed when their house exploded. A neighbor, 29-year-old Jessica Teague, also died. The Hites died of blunt force trauma to their chests, while Teague died of compression asphyxia, the Vanderburgh County Coroner’s Office said.

Mike Larson, the division chief of the Evansville Fire Department, said Wednesday that he hopes the findings bring closure to all the people who were affected by the explosion.

“The investigation is complete, these are the findings and hopefully it will help everybody be able to move forward from this point,” he said.

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