An inmate who died in his prison cell while serving life at an Oklahoma penitentiary for murdering an eight-year-old was strangled to death, officials said.

Anthony Palma, 59, died January 11 from “ligature strangulation and blunt force trauma to the head” in his Oklahoma State Penitentiary cell, according to a report from the Office of the State Medical Examiner obtained by the Associated Press.

Palma, who was serving life in prison without parole for murdering and abducting eight-year-old Kristen Hatfield in 1997, was strangled to death by his cellmate, Raymond Pillado. Pillado was also serving time for murder.

Hatfield had been kidnapped from her Midwest City, Oklahoma, home shortly after going to bed the night of May 13, 1997.

A court eventually found Palma guilty of kidnapping, sexually assaulting, and murdering the eight-year-old before disposing of her body in an undisclosed location.

Hatfield’s body was never found.

Palma lived two houses away from the Hatfield family and had been arrested in 2015 in connection with Hatfield’s cold case murder after DNA testing determined his sample matched evidence linked to Hatfield’s abduction.

“We’ve not had closure on this case and we may never have closure because we wanted to find her body and bring her home,” Midwest City Police Chief Brandon Clabes said. “Our hopes are, with any case like this, the suspect who’s convicted… in this case, it was Anthony Palma… that hopefully he would have some inkling of a conscience, maybe intervention by a higher power, maybe God, and come out and tell us exactly what he did with her.”