Lydia Kaiser, 12, has been healing at home for over a week after being released from the hospital following the Aug. 27 Annunciation school shooting.

A teen who opened fire in a Colorado high school this week was active on a so-called "violent gore" site months before the attack, the Anti-Defamation League said in a report released Friday.

Two teenagers are in critical condition after another teenager, who has since died, is suspected of opening fire in a Colorado high school, according to authorities. The suspected shooter has been identified as Desmond Holly, said Jacki Kelley, spokesperson for the Jefferson County Sheriff's Office, during a Thursday, Sept. 11 news briefing.

Annunciation Catholic School will resume limited activities, three weeks after a mass shooting that killed two children and injured 21 people.

Pennsylvania State Police troopers are investigating a shooting in Aliquippa, Beaver County, on Thursday evening.

A boy who allegedly fired a gun during a fight in Fairfield High School’s parking lot turned himself in to police on Wednesday. “A juvenile suspect was identified as the shooter and a warrant was issued for his arrest.

Experts say a teenager suspected in a shooting attack at a suburban Denver high school that left two students in critical condition appeared fascinated with previous mass shootings including Columbine and expressed neo-Nazi views online.

Three Columbus City schools were placed on lockdown following the shooting, which was reported at around 3 p.m. and resulted from a fight.