Fire crews didn’t find working smoke or carbon monoxide detectors in the residence but said the business below had a smoke detector.

COALPORT, Pa. (AP) — A malfunctioning coal-burning furnace is to blame for the deaths of three family members whose bodies were found in a central Pennsylvania home over the weekend, authorities said.

State police in Clearfield County said the problem caused carbon monoxide to leak into the Coalport residence, killing 67-year-old Robert McClellan, his 57-year-old wife, Brenda, and her 68-year-old brother, Ronald Jasper.

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The owner of a business below the residence called 911 Saturday after finding the building full of smoke. The Glendale Volunteer Fire Department responded at 10:15 a.m. Saturday but found the victims dead. Assistant Fire Chief Hugh Yeckley said they are believed to have died sometime during the night.

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The county coroner’s office conducted toxicology tests and said results won’t be back for several weeks, but Coroner Kim Shaffer-Snyder said nothing was found to lead her to believe there was any other reason for the victims’ deaths.

Fire crews didn’t find working smoke or carbon monoxide detectors in the residence but said the business below had a smoke detector.

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