Teenage gunman T.J. Lane was sentenced Tuesday to life in prison without the possibility of parole for killing three teens at his high school last year in Chardon, Ohio.

Lane, 18, gave the middle finger to the victims' families and unbuttoned his shirt to reveal a white T-shirt with the handwritten word "killer" on it during the sentencing hearing. He originally pleaded not guilty by reason of insanity but changed his plea to guilty last month.

The teen waived his right to have attorneys present any evidence during the sentencing hearing, so the victims’ families got to do all the talking.

One of the victim’s moms, Holly Walczak, told Lane he is lucky there were so many officers in the room to protect him. The mom of victim Danny Parmertor told Lane he was a monster, not even a human being.

Read more: Chardon victim says, 'Students are trying to move on'

Lane smirked and smiled throughout the sentencing, according to HLN affiliate WJW. He even reportedly laughed as the prosecutor called him an “evil person.”

Daniel Parmertor, 16, Demetrius Hewlin, 16, and Russell King, Jr., 17, were all killed when Lane opened fire in the school cafeteria with a .22 caliber gun. Joy Rickers and Nick Walczak were hurt while another student was grazed by a bullet.

Lane was charged with three counts of aggravated murder, two counts of attempted aggravated murder and weapons-related charges.  

Follow along with a live blog of the hearing from HLN affiliate WJW.

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