The mystery behind the disappearance of 5-year-old Elijah Lewis ended tragically last month as officials identified remains found in Massachusetts as the missing New Hampshire boy.
But what exactly happened to him? Until this week, authorities had said little about what caused his death.
Here's a look back at what we know about the case:
When was Elijah Lewis last seen?
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Elijah was last seen at his home in Merrimack, New Hampshire, sometime within 30 days of when he was officially reported missing on Oct. 14.
The attorney general's office had initially said Elijah was last seen about six months ago before revising their statement.
When did authorities realize the child was missing?
The New Hampshire Division for Children Youth and Families notified police on Oct. 14 that Elijah was missing.
The agency’s involvement with the boy is unclear, but state police said he was last seen by “independent individuals” and was never reported missing to authorities before this month.
Mother, another man arrested
Elijah's mother, Danielle Dauphinais, 35, and her boyfriend, Joseph Stapf, 30, were arrested Oct. 17 in New York and remain held without bail on charges of witness tampering and child endangerment. They are both scheduled to return to court in December.
No one has been charged with causing Elijah's death. Prosecutors had said previously that they were waiting for the autopsy results before moving forward with charges in the boy's death.
The witness tampering charges allege that they each asked other people to lie about Elijah and where he was living, knowing that child protection service workers were searching for him. The endangerment charges allege that they violated a duty of care, protection or support for Elijah. Court affidavits supporting the charges were sealed.
Search comes to a tragic conclusion
A state police cadaver dog found Elijah's body buried in a makeshift grave in the woods in Abington, Massachusetts — about 20 miles south of Boston — a little over a week later on Oct. 23.
It's unknown how long the body had been in the woods. Multiple agencies from New Hampshire, Massachusetts, Rhode Island and Maine helped with the search.
The search shifted to Abington from New Hampshire based on a tip. Previous searches in the area around Elijah's New Hampshire home by helicopter and a nearby lake by boat had turned up nothing.
Plymouth County District Attorney Timothy Cruz and other law enforcement officials shared few details about the case after the body was found, saying they didn't want to say anything that would jeopardize getting justice for Elijah.
"Obviously a little boy is gone. Nobody deserves to die this way and we hope to get justice for the little boy," Cruz said at the time.
What did the autopsy results show?
The New Hampshire Attorney General's Office released Elijah's cause of death on Nov. 22. They showed that the young child died of violence and neglect, including facial and scalp injuries, acute fentanyl intoxication, malnourishment and pressure ulcers.
The autopsy results were the first time authorities had said anything about how Elijah died.
The attorney general's office said the investigation into Elijah's death "remains active and ongoing" and asked anyone with information to contact police.
"This has multiple findings that are all contributing to his death," Senior Assistant New Hampshire Attorney General Susan Morrell said. "If anybody has additional information about Elijah's life in Merrimack or his death, we'd really like them to reach out to law enforcement."