Desmond Holly, the suspected shooter who critically injured two students at Evergreen High School in Colorado on Wednesday, shared antisemitic and white nationalist views online, according to the Denver Post and the Anti-Defamation League.

Local authorities said Thursday that Holly had been “radicalized by some extremist network,” without specifying further.

According to the Denver Post, one of Holly’s online accounts used a coded slogan for Holocaust denial and reposted antisemitic videos and other videos showing individuals in Nazi uniforms.

The ADL’s Center on Extremism said Friday that Holly’s TikTok accounts were “filled with white supremacist symbolism,” including a reference to the white nationalist “14 words” slogan, and utilized a neo-Nazi symbol in his profile photo.

The ADL reported that Holly, in online interactions, shared photos of patches he had created featuring neo-Nazi symbols, similar to those used by prior mass shooters. He also shared a photo of himself in a mask that featured multiple white nationalist symbols and slogans, including “TJD” — standing for “Total Jew Death.”

According to the ADL, Holly collected tactical gear — inspired in some cases by past mass shooters — which he decorated with extremist symbols, posted internet content mimicking prior shooters and suggested in online comments that he was preparing to carry out an attack. 

His accounts included numerous references to Brenton Tarrant, the far-right killer who murdered 51 at two mosques in New Zealand, among other mass killers.

Holly also maintained an account on an internet forum where users share images and footage of various deaths and murders, and commented on posts about past mass shootings, according to the ADL research. The platform has been used by multiple prior mass shooters.

Similar fascinations with extremist and antisemitic views and prior school shooters, as well as apparent interactions with online extremist networks, have been a feature of several recent mass attacks.

“The deeply disturbing specifics of this case follow a pattern recently discovered by ADL Center on Extremism, which its analysts have found in at least three school shootings committed by young people over the past year,” the ADL report stated, including engagement with some of the same online forums.

The Colorado shooting took place shortly after the killing of right-wing influencer Charlie Kirk in Utah.