“The cause of Elijah’s death was determined to be violence and neglect, including facial and scalp injuries, acute fentanyl intoxication, malnourishment and pressure ulcers,” a medical examiner determined via CBS Boston.
Lewis' body was discovered in what investigators referred to as a grave at Abington Park on October 23, nine days after the 5-year-old was reported missing by Department of Children, Youth and Families officials on October 14.
Elijah's mother, Danielle Dauphinais, 35, and her boyfriend, Joseph Stapf, 30, were both arrested on child endangerment and witness tampering charges three days after the child's remains were located and are being held without bond.
The witness tampering charges stem from evidence showing Dauphinais and Stapf allegedly telling other individuals to lie about Lewis' whereabouts and where he was living with knowledge that child protection services were looking for the 5-year-old, the attorney general confirmed in a statement released last month.
Local authorities began investigating Lewis' death and were joined by the New Hampshire State Police and the New Hampshire Department of Justice, the state's Attorney General's Office confirmed.
New Hampshire Senior Assistant Attorney General Susan Morrell told WMUR last month that Lewis -- who was not reported missing prior to the DCYH's involvement on October 14 -- is believed to have initially disappeared as early as September 1.