FITCHBURG, Mass. (AP) — Authorities say the death of a 5-year-old boy whose remains were found wrapped in a blanket and packed in a suitcase by the side of a Massachusetts highway has been ruled a homicide.

Worcester County District Attorney Joseph Early Jr.’s office said Thursday that an autopsy report conducted by the Office of the Chief Medical Examiner ruled Jeremiah Oliver‘s cause of death homicidal violence of undetermined causes.

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The Fitchburg boy’s remains were found in April 2014 on Interstate 190 in Sterling after he was missing for months.

The body was found just off Route 190 in Sterling in April 2014. (WBZ-TV)

The body was found just off Route 190 in Sterling in April 2014. (WBZ-TV)

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His mother, Elsa Oliver, and her boyfriend, Alberto Sierra, were indicted in 2014 on assault and kidnapping charges. They both pleaded not guilty.

Elsa Oliver in court, December 2013. (WBZ-TV)

Elsa Oliver in court, December 2013. (WBZ-TV)

No one has been charged with the boy’s death. Officials say the investigation is ongoing.

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