Bethel, CT – A 79-year-old woman found dead in her home last week is believed to have been a victim of accidental carbon monoxide poisoning, police said Monday.

Mary Adelman, of Lexington Boulevard, apparently left her car running in the garage beneath her unit at the Lexington Meadows condominiums when she returned home Wednesday, said Capt. Robert Cedergren.

The car was still running when police, who were asked to check on Adelman by her husband, gained entry to the unit at noon Thursday and found her in the bedroom.

A “high level of noxious fumes” had filled the condominium by the time police got in, Cedergren said. Fire department personnel were summoned to ventilate the unit.

“She was determined to be deceased at the scene,” Cedergren said.

Exhaust fumes had also infiltrated the neighboring unit, but its owner wasn’t home. He was later examined by his own doctor.

Police are awaiting a report from the medical examiner before concluding their investigation.

“But at this time it appears to have been an accident,” Cedergren said.