17-year-old sentenced to life in prison for death of 10-year-old Colorado girl
KDVR / Adams County
Aidan Zellmer, Kiaya Campbell

via KDVR:

BRIGHTON, Colo. (KDVR) -- The teenager who pleaded guilty last month to killing a 10-year-old Thornton girl was sentenced to life in prison on Monday with the possibility of parole after 40 years.

Aidan Zellmer, 17, was charged as an adult in the death of Kiaya Campbell on June 7, 2017, after they left her father’s home to go to a shopping center. It was originally reported Zellmer is 16; he is 17.

“In 27 years as a prosecutor, I have never seen a 15-year-old commit such a violent act,” 17th Judicial District Attorney Dave Young said.

Neighbors found her battered body in a ravine the next day. She had been beaten to death, according to an Adams County Coroner’s Office autopsy report.

In court on Monday, it was revealed that Zellmer hit Campbell in the head five times with a metal pipe and dragged her into a ditch, leaving her there to die.

Two days later, officers arrested Zellmer, who was 15 at the time and lived in the same home in Thornton.

His mother was in a relationship with Campbell’s father at the time.

Zellmer was facing four counts of first-degree murder, two counts of sexual assault and one count of sexual assault on a child. All of the charges were dropped with the guilty plea.

MORE: 16-year-old sentenced to life in prison for death of 10-year-old Thornton girl - KDVR