A Michigan man who spent 16 years behind bars for killing his pregnant wife in 1991 pleaded guilty Wednesday to the murders of four children, including his own two daughters, PEOPLE confirms.
According to court records obtained by PEOPLE, Gregory Green admitted before a Wayne County judge that he killed his two daughters and his stepdaughters in late September — eight years after his release from prison for his first wife’s stabbing death.
Accepting a plea deal from prosecutors, Green pleaded guilty to manslaughter, torture and assault for the Sept. 28. 2016, crime.
According to court records, Green, 49, fatally shot his stepchildren — 19-year-old Chadney Allen and 17-year-old Kara Allen — in front of their mother, Faith Green. Faith Green was stabbed and shot but survived the attack inside the couples’ Dearborn Heights residence.
Green’s own daughters — Kaleigh, 4, and Koi Green, 5 — both died from asphyxiation caused by carbon monoxide poisoning. Records verify that Green placed them in a car; toxic fumes from the tailpipe were routed into the vehicle through a plastic hose.
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Afterwards, Green moved his daughters’ bodies into their beds.
Green called 911 not long after the murders and admitted he had killed his entire family. Police found him waiting for them on his front porch.
Inside, officers found Faith Green bound with duct tape and zip ties. Green cut his wife’s face with a box cutter before shooting her foot. He shot his two stepdaughters multiple times as their mother watched.
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According to court records obtained by PEOPLE, Faith Green had filed for divorce a month before the murders, citing a “breakdown in the marriage relationship.”
Green pleaded no contest to his first wife’s 1991 murder. He was released in 2008.
Green will be sentenced on March 1.