TJ Lane was sentenced today to life in prison without parole for last year's deadly Chardon High School shooting in Ohio.
Lane, 18, came to his sentencing in a white T-shirt with the word "Killer" on it and smirked as family members of the victims read their statements, WEWS reported.
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He also swore and flipped off the victims' families during his statement to the court.
"This hand that pulled the trigger that killed your sons now masturbates the memory. F*** all of you," Lane said.
Family members of his victims described his disregard for them and the law as "repulsive" and hoped for him to be locked up in a cage "like an animal" for the rest of his life, ABC News reported.
"You don't deserve to be called human. You're a monster," the mother of shooting victim Daniel Parmertor told him.
Prosecutor .. expressed shock also when he gave the families of the 3 people who murdered the finger.
"This is confirming what we have known all along, that this was a cold, calculated, premeditated killing," the prosecutor said.
Lane pleaded guilty in February to three counts of aggravated murder, attempted aggravated murder and felonious assault in the attack last February.
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He originally entered a plea of not guilty by reason of insanity, The Plain Dealer reported.
Prosecutors say Lane took a .22-caliber pistol and a knife to the school and sprayed bullets at a group of students in the cafeteria.
According to investigators, Lane has admitted to the shooting and believed he had "killed a bunch of people," but doesn't know why he did it.
Parmertor, Russell King Jr. and Demetrius Hewlin died as a result of the shooting. Three more students, Nick Walczak, Nate Mueller and Joy Rickers, were injured.
Dina Parmertor, mother of victim Daniel, said Lane was "a pathetic excuse for a human being" and hoped he suffered "an extremely, slow torturous death," AP reported.
She said she lived with the pain and torment every day, suffering nightmares and being physically sick over the shooting.
"From now on, he will only be a killer," she said, as Lane's smile widened. "I want him to feel my anger toward him."