Investigators said on Friday a teen gunman accused in the Kentucky high school shooting viewed it as a “science experiment.”

Investigators said Gabriel Parker, who is accused of fatally shooting two high school classmates and hurting several others, didn’t show any remorse.

According to the Marshall County Sheriff’s captain, Parker told police he was interested in science and he wanted to see how students, police and society would react to the shooting.

The captain also described 15-year-old Parker as “cold and callous” and that he didn’t show any emotion during a police interview.

Parker is said to have told police no event triggered the shooting and that he was not bullied at school. The teen, according to police, said he was an atheist and believed no one’s lives have a purpose.

Kentucky State Police detective, David Dick, testified Parker contemplated shooting himself in December, but realized his family would hurt more if he killed himself rather than if he just went to prison for harming someone else.

Authorities said Parker, who played trombone, went to the band room on Jan. 23 to make sure his friends were safe before going to a common area where he began firing.

Another hearing in the case is set for Monday.

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