The teenager charged with killing four people and injuring others during a shooting spree last month at Apalachee High School entered a not guilty plea, according to Barrow County court records.

Colt Gray, 14, also waived his arraignment, or a formal reading of his charges in a courtroom, and requested his case go to trial, a document filed Tuesday states.

The move comes days after both Gray and his father, Colin Gray, were indicted by a Barrow grand jury.

Colt Gray was indicted Thursday on 55 charges in the Sept. 4 mass shooting. His charges include: four counts of felony murder, four counts of malice murder, four counts of aggravated battery, 18 counts of cruelty to children in the first degree and 25 counts of aggravated assault.

Christian Angulo and Mason Schermerhorn, both 14-year-old students, and teacher Cristina Irimie and coach Richard Aspinwall were killed in the shooting. There were a total of 25 victims, according to the indictment.

Colin Gray is facing 29 charges for providing his son with the gun, including: two counts of murder in the second degree, two counts of involuntary manslaughter, five counts of reckless conduct and 20 counts of cruelty to children in the second degree. He is scheduled for arraignment Nov. 21 and remains in the Barrow jail without bond.

According to the indictment, Colin Gray allowed Colt “access to a firearm and ammunition after receiving sufficient warning that Colt Gray would harm and endanger the bodily safety of another” and caused “with criminal negligence” the death of the four victims.

During a recent hearing, GBI agents testified that Colt Gray wrote plans for the mass shooting in a notebook and used a rifle that his father had given him for Christmas.

The next court date for Colt Gray has not been scheduled. He remains in custody.

Apalachee students returned to class for half-days Sept. 23 and then went back full time Oct. 14 after fall break.