Desmond Holly’s focus on the 1999 massacre at Columbine High School is a central feature of these online extremist ecosystems ...

Police suspect the teenage gunman who carried out a school shooting in Colorado this week was “radicalized” before injuring ...

The 16-year-old boy who shot two schoolmates and then himself at Evergreen High School was “radicalized by some extremist ...

A rapid lockdown kept the shooting at Evergreen High School outside of Denver from ending in more bloodshed, authorities say.

One student remains in critical condition following a shooting at Evergreen High School on Wednesday that left two students ...

Investigators said Thursday that they have identified the shooter responsible for the Wednesday afternoon shooting at ...

Since December, Desmond Holly, 16, had been active on an online forum where users watch videos of killings and violence, ...

The Colorado high school shooting suspect, who was identified as a 16-year-old student, was believed to be "radicalized by some extremist network,” officials said.

A 16-year-old student was believed to be "radicalized by some extremist network," officials with the local sheriff's office ...

Authorities have identified the boy suspected of shooting two fellow students, before fatally shooting himself at Evergreen ...

The Jefferson County Sheriff’s Office identified the student suspected of shooting two students and himself on Wednesday at ...

Authorities in Colorado identified the suspect Thursday as a 16-year-old student and said he died of a self-inflicted gunshot ...