Investigators have determined that the shooting deaths of a northwestern New Jersey couple and their adult son last weekend was a double murder and suicide carried out by the son.

Hunterdon County Prosecutor Anthony Kearns III announced the findings Tuesday afternoon.

Kearns said autopsies determined that 62-year-old Andrew Wierzbicki; his 56-year-old wife, Wanda, and their 26-year-old son, Gabriel, all died of gunshot wounds. The couple's deaths were both ruled as homicides, while their son's death was ruled a suicide.

Citing the medical evidence, Kearns said investigators believe Gabriel Wierzbicki killed himself after both of his parents had died, but did not provide further details.

Kearns said there was no sign of a forced entry into the family's Kingwood Township home, where the bodies were found late Saturday morning.

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