(MANCHESTER, N.H.) — The father of Harmony Montgomery, a little girl who disappeared in 2019, was arrested on Monday for her murder, New Hampshire officials said.

Adam Montgomery, 32, is charged with second-degree murder, tampering with a witness, falsifying evidence and abuse of a corpse, New Hampshire Attorney General John Formella announced at a news conference Monday.

Prosecutors allege Adam Montgomery repeatedly hit his daughter in the head on or about Dec. 7, 2019. The tampering with a witness charge is for allegedly pressuring his wife to give false information, prosecutors said.

This August, authorities announced they had determined Harmony had been murdered in Manchester in early December 2019.

Harmony’s remains have not been found. She would be 8 years old if alive today.

Manchester Police Chief Allen Aldenberg became choked up when talking about Harmony at Monday’s news conference.

In honor of Harmony — an “innocent and defenseless child” — the chief said he wanted to encourage people “to do something nice for a child today.”

“Give him or her a hug, some special words of encouragement,” he said.

Formella called the arrest a “major step,” but said more work must be done.

Harmony’s case dates back to 2019, when a Massachusetts court ordered Harmony be sent to live with her father and stepmother in New Hampshire, according to a state report released in February.

Harmony’s mother, Crystal Sorey, said the last time she saw Harmony was via FaceTime in spring 2019, officials said.

In July 2019, an anonymous call was made to New Hampshire’s Division for Children, Youth and Families alleging that in a visit a week earlier, he or she saw Harmony “had a black eye that Adam Montgomery admitted to causing,” the report said. The same day as the anonymous call, a case worker visited and didn’t see a black eye on Harmony, the report said.

One week later, that same case worker noted a red mark and faded bruising under Harmony’s eyelid, and both Harmony and her dad told the worker the mark was from being hit by a toy while playing, the report said.

In following visits to the home, “the children appeared happy and healthy,” the report said. In the last visit, in October 2019, case workers found the abuse allegations unfounded but added, “the situation was scored high risk for future child welfare involvement pursuant to the Risk Assessment tool citing the history of substance use, prior family history with child protection, and economic challenges,” according to the report.

In January 2020, Adam Montgomery told the child protective services worker that Harmony had been living in Massachusetts with her mother since Thanksgiving 2019, the report said. The worker left a voicemail with Sorey to confirm Harmony lived there, but never heard back, the report said.

In September 2021, someone close to Harmony’s mother contacted the Division for Children, Youth and Families with concerns, and the agency determined Harmony had never been registered for school in Manchester, the report said.

The Division for Children, Youth and Families then searched for Adam and Kayla Montgomery.

When police found Adam Montgomery in December 2021, he gave the authorities “contradictory and unconvincing explanations of Harmony’s whereabouts,” the report said. Adam Montgomery allegedly told police Harmony’s mother had picked her up, even though Kayla Montgomery told police that Adam Montgomery told her he drove Harmony back to her mother on the day after Thanksgiving 2019, according to the report.

Adam Montgomery is expected to be arraigned on Tuesday, Formella said.

Authorities urge anyone with information on Harmony’s death or the location of her remains to call or text the case’s tip line at 603-203-6060.

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