NORTH HAVERHILL, N.H. (AP) — Three gas fitters have been indicted on negligent homicide charges in the 2019 carbon monoxide poisoning deaths of a couple in their New Hampshire home.

State police who went to the Lyman home of John Courtney, 71, and April Courtney, 63, in January 2019 found them dead, along with several cats and dogs. The state medical examiner’s office ruled the cause of death to be accidental due to carbon monoxide poisoning.

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Grafton County indictments released this week accused three licensed gas fitters of improperly installing gas boiler and vent system equipment in their home.

Richard Mallett Jr., 49, of Woodsville, New Hampshire, and Philip Poirier, 28, of Corinth, Vermont, are each charged with two felony counts of negligent homicide and one felony count of reckless conduct alleging that they negligently, recklessly and improperly installed heating equipment that cycled exhaust gases back into the home, where the gases reached fatal levels.

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Adam Vigent, 51, of North Haverhill, New Hampshire, also was charged with two felony counts of negligent homicide, accusing him of directing the improper installation of the equipment.

A message seeking comment was left at a possible number for Vigent. Phone numbers couldn’t be found for the others. It was not known if any of them had lawyers.

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