BRIGHTON, Colo. (CBS4) – The judge in the case of a child homicide allegedly at the hands of a teenager, has entered a plea of “not guilty” for the 15-year-old boy.

Aiden Zellmer has been charged as an adult in the killing of the 10-year-old girl last summer.

Aidan Zellmer (credit: CBS)

Kiaya Campbell’s body was found last June in a drainage ditch near her home in Thornton.

Kiaya Campbell (credit CBS)

The Adams County coroner says she died from blunt force injuries to the head due to an assault. There were many lacerations and fractures to her head that caused her death.

Officials decided Zellmer will be tried as an adult in January. On Tuesday, the judge entered a plea for him.