The father of missing 5-year-old Harmony Montgomery has been hit with eight new charges related to gun thefts from late 2019, on top of the allegations the man already faces, officials announced Monday.

Adam Montgomery, a drug-addled career criminal with rap sheets in at least Massachusetts and New Hampshire, was charged with two counts each of four charges related to a rifle and a shotgun and his alleged theft or use of each despite his felony conviction history, according to New Hampshire Attorney General John Formella

Montgomery, 32, remains behind bars and is expected to be arraigned on the new charges Tuesday in Hillsborough County Superior Court’s Northern District. Investigators have not found evidence to link either stolen firearm to the disappearance of 5-year-old Harmony, they said. 

MISSING HARMONY MONTGOMERY: JAILED DAD'S GIRLFRIEND FOUND DEAD IN MANCHESTER, NEW HAMPSHIRE

Adam Montgomery, who police arrested on child abuse and endangerment charges in connection with an alleged assault on his daughter from 2019 and her disappearance.  (Manchester Police)

Police began searching for Harmony and her father in December 2021, after learning that the girl had not attended school in the two years that Adam held full custody.

They found Adam Montgomery living out of a car in Manchester, New Hampshire, on Dec. 31.

After police questioned Montgomery, they alleged he gave them contradictory statements – including first claiming to have recently spoken to Harmony and then backtracking to claim that the last time he saw Harmony was when her biological mother picked her up, sometime around Thanksgiving 2019.

MISSING HARMONY MONTGOMERY: TIMELINE OF EVENTS

Then he allegedly stopped answering questions and told investigators, "I have nothing else to say … If I’m not under arrest, I’m leaving."

He was arrested four days later. Harmony has not been found.

Montgomery and his estranged wife, Kayla Montgomery, are being held on separate charges in the case. Accusations against the father include child abuse for allegedly giving the partially blind child a black eye in 2019. Kayla Montgomery allegedly committed welfare fraud by collecting food stamps in Harmony’s name for months after she’d last seen the child.

MISSING HARMONY MONTGOMERY: DAD ACCUSED OF GIVING PARTIALLY BLIND DAUGHTER BLACK EYE IN 2019, OTHER ABUSE

The charges announced Monday against Adam Montgomery are for:

  • Unauthorized taking for stealing the rifle and the shotgun;
  • Receiving stolen property for receiving or retaining the rifle and the shotgun;
  • Felon in possession of rifle and shotgun after having been convicted of one or more qualifying felonies;
  • Armed career criminal for possessing the rifle and the shotgun after having been convicted of three or more qualifying felonies.

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Harmony is described as being 4-feet-tall and weighing around 50 pounds, with blonde hair and blue eyes. She would likely be wearing glasses and is blind in her right eye.

Anyone with information on her is asked to call the Manchester Police Department’s Harmony Montgomery tip line at 603-203-6060.