Acting Morris County Prosecutor Fredric Knapp issued the finding Tuesday, one day after the fire roared through the Mount Olive residence. He also said the unit had no working smoke detectors.
Knapp said 52-year-old Hesham Moustafa and 7-year-old Cristiano Bonner were killed in the fire.
The boy's mother, Carmella Moustafa, and her 9-year-old daughter, Bianca Bonner, were both injured in the fire, while Hesham Moustafa's 19-year-old daughter, Rewan Moustafa, safely escaped the flames.
Bianca Bonner remains hospitalized in stable condition, while her mother was treated and released.
The fire was ruled an accident.
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