Fire That Killed 5 Children in Pennsylvania Daycare Was Caused by Faulty Extension Cord

The fire that killed five children in an overnight Pennsylvania daycare in August was sparked by a faulty extension cord, an investigation has revealed.

The Harris Family Day Care blaze in Erie, which erupted in the early hours of Aug. 11, was formally declared an accident by investigators from the Bureau of Alcohol, Tobacco, Firearms and Explosives, the Allegheny County Fire Marshal’s Office and the Erie Police and Fire Departments.

“Based upon data collected during this investigation and the subsequent analysis of that data, it is the combined opinion of the fire scene investigation team that the fire was caused by an electrical failure associated with a routinely-used extension cord” in the living room, the ATF said in a statement obtained by NBC News Thursday.

No criminal charges are pending, ATF Special Agent Charlene Hennessy told the outlet.

“The integrity of the wiring was compromised,” she said. “There was a faulty wire inside of the extension cord.”

Hennessy did not immediately respond to PEOPLE’s request for comment.

The official cause comes after a spokesperson for the Lawrence Park Volunteer Fire Department speculated to PEOPLE in August that over-loaded extension cords could be to blame, as there were several of them located underneath a carpet that was sitting under a couch where the fire originated.

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“There was only one smoke detector and that was in the attic,” he said. “By the time the smoke got to the smoke detector in the attic, it was too late.”

Five children were killed in the blaze, four of whom were siblings.

Three of those siblings shared the same father: Lawrence Park Volunteer firefighter Luther Jones, 29, who was responding to an automatic fire alarm when the daycare flames erupted.

The Erie Fire Department responded to the daycare incident, and it wasn’t until hours later that Jones received the tragic news that three of his children had died.

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“I can’t imagine what that poor young man is going through,” Lawrence Park Fire Chief Joe Crotty told PEOPLE at the time. “The poor kid. We’re doing everything we can. We all went over as a fire department and brought him food and sat down and talked with Luther.”

Shevona Overton told CBS affiliate told WSEE that the four siblings were her children, identifying them as La’Myhia Jones, 8; Luther Jones Jr., 6; Ava Jones, 4; and 9-month-old Jaydan Augustyniak.

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“I’m just so hurt my babies are gone,” Overton told WSEE. “I love them dearly. I just hurt inside knowing that my kids were fighting and hurting in that fire. Every minute, I feel the same pain.”

Two teenagers in the home managed to escape through a second-story window, and suffered injuries from broken glass. A next-door neighbor was also injured, and suffered minor burns after she tried unsuccessfully to enter the building.

Elaine Harris, the owner of the daycare, suffered burns as she tried to escape, and was later injured in a car crash after leaving the location.