Prosecutors Reveal New Details in Death of 5-Year-Old Jeremiah Oliver

Prosecutors allege that the boy died in September 2013 and that his mother marked the date of his death in a journal

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Nearly a decade after 5-year-old Jeremiah Oliver's body was found in a suitcase on the side of a highway, prosecutors are releasing new details about how and when he died.

Alberto Sierra Jr., 32, the former boyfriend of Jeremiah's mother, Elsa Oliver, is facing murder charges in Jeremiah's death. At a hearing at Worcester Superior Court Wednesday, Assistant District Attorney Courtney Sans revealed new details that she said investigators have uncovered in the years since Jeremiah's body was found on the side of a highway in 2014.



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Jeremiah, who was from Fitchburg, was last seen alive in September 2013, but wasn't reported missing until December of that year. His body was found off Interstate 190 in Sterling in April 2014. His death was not ruled a homicide until February 2016 when an autopsy by the state medical examiner said that he died of "homicidal violence of undetermined" causes.

According to the prosecution, witnesses have come forward over the years, painting a picture of a violent relationship between the defendant and Jeremiah's mother. Sans said Jeremiah's mother eventually revealed to investigators that in September 2013 she and Sierra were in a fight at their home. Elsa Oliver said that Sierra headbutted her, and when she went to clean up Jeremiah, who was in a kitchen closet, came out and said something to the effect of "don't hurt my mommy." That was when, prosecutors claim, Sierra slammed the child's head into the floor. Oliver said her son was not moving, and when she tried to intervene, she was attacked and eventually passed out.

The prosecution noted that Jeremiah was often left in the kitchen closet because of "perceived issues with discipline." Sans said Jeremiah was placed back in the closet after the attack and the next day he was not breathing. The apparent date of his death was written in a journal kept by his mother.

The prosecution further alleges that Sierra put Jeremiah's body in a bag and left it in a hole, but later became concerned in December when the community began looking for the missing child. Prosecutors allege that Sierra, with the help of others, moved the body several times.

Sierra has pleaded not guilty to the two charges against him-- murder and disinterring of a body. A Worcester grand jury returned indictments against him. A judge ordered him held without bail Friday.

The prosecution had requested that result. Defense attorney Marissa Elkins had requested his release, with conditions including GPS monitoring, pointing out he has significant ties to the Fitchburg and Leominster area, and said his past behavior on probation, as well as his awareness of the nature of the long investigation against him, shows no indications that he would fail to show up for the case. She also pointed out that he has been diagnosed with rheumatoid arthritis and would be unable to continue in a clinical trial if he remains in jail.

The next court date was set as a June 28 pretrial conference.

While Sierra was never brought up on murder charges before this, he has served time related to violence against Jeremiah's mother and siblings. He was sentenced to as many as seven years in prison back in 2017 after pleading guilty to abusing Jeremiah's siblings and mother. Elsa Oliver pleaded guilty to endangering the boy's siblings and abusing one of them and was sentenced to seven and a half years in prison.

Both were released in 2020, according to the Sentinel & Enterprise.

Sans said witnesses reported the relationship between Sierra and Oliver was often violent and that Oliver expressed that she was afraid of sierra.

Sierra's brother, Christian Sierra, was also charged with lying to police about the investigation, along with two others.

Prosecutors had dropped charges of kidnapping and assault of Jeremiah against Sierra and Elsa Oliver at the time so double jeopardy did not apply as they continued to pursue homicide charges. It's unclear whether prosecutors also plan to indict Elsa Oliver.

(Fitchburg, MA 05/03/14) Mourners enter Rollstone Congregational Church for the funeral of Jeremiah Oliver on Saturday, May 03, 2014. Staff photo by Patrick Whittemore. (Photo by Patrick Whittemore/MediaNews Group/Boston Herald via Getty Images)

The boy’s death sparked a major review of the state’s Department of Children and Families, which eventually underwent an overhaul. Several of the DCF workers assigned to Oliver’s case were fired after it was revealed they had missed visits and appointments.

The Associated Press contributed to this report.

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