The FBI said it received a tip in July about troubling online posts linked to the Colorado high school student who is accused of shooting two classmates before taking his own life, but investigators were unable to identify the account user before the attack and therefore took no federal enforcement action.
The shooter, identified by local authorities as 16-year-old Desmond Holly, struck one student inside Evergreen High School and another outside the campus on Sept. 10. Holly died of an apparent self-inflicted gunshot wound following the incident, Jefferson County authorities said. The FBI confirmed to Fox News Digital that it had been made aware of the online activity several months earlier but that the account holder’s identity remained unknown during the bureau’s assessment.
“We continued to work this assessment investigation to identify the name and location of the user up and until September 10, 2025,” the FBI said in a statement. “During the assessment investigation, the identity of the account user remained unknown, and thus there was no probable cause for arrest or additional law enforcement action at the federal level.” The agency said the Denver field office was coordinating with partner agencies as the probe into the shooting continued.
The Anti-Defamation League’s Center on Extremism said it examined Holly’s online activity and found posts and accounts that reflected neo‑Nazi views and an interest in past mass shootings. The ADL reported that Holly had commented on a gore forum called WatchPeopleDie about incidents including the Parkland, Fla., shooting in 2018 and the Buffalo, N.Y., attack in 2022, and that he posted material emulating the 1999 Columbine shooters and others.
ADL researchers said the teen collected tactical gear, displayed extremist symbols on that gear and posted content invoking white supremacist slogans. TikTok told The Associated Press that accounts associated with Holly had been banned. The name of one of his most recent TikTok accounts reportedly included a reference to a popular white supremacist slogan; that account was unavailable on Friday, the ADL said.
Jefferson County Sheriff’s Office spokesperson Jacki Kelley said during a news conference that investigators were still determining whether the victims were singled out or shot at random. The county, which includes the Denver suburb of Evergreen, was also the site of the 1999 Columbine High School massacre.
St. Anthony Hospital in Lakewood, which had been treating the two victims, did not immediately respond to a Fox News Digital inquiry about their conditions. Local law enforcement has not released further details about motive, and the sheriff’s office previously said Holly had been radicalized by an unspecified “extremist network,” without providing additional information.
Concerns about the role of online platforms in spreading extremist content have intensified as officials and advocacy groups probe the shooting. The ADL warned that young people can readily access extremist content and graphic depictions of violence that may be celebrated by users, potentially desensitizing viewers and increasing the risk of ideologically motivated violence.
Sen. Chris Coons, D-Del., told CBS’ Face the Nation on Sunday that the internet was “driving extremism in our country,” comments that followed broader national attention to the circulation of extremist and violent content online after recent political violence and high-profile killings.
FBI leadership said agents were continuing to cooperate with local and state partners in the investigation. The bureau did not immediately respond to a Fox News Digital request for additional comment on the timeline of its assessment or the nature of the original tip. Fox News Digital and The Associated Press contributed reporting to the developments summarized here.
Investigators are continuing to examine the shooter’s digital footprint and any connections to online networks identified by the ADL and local authorities. Federal officials have said the inability to link online accounts to a known individual can limit what actions the FBI can take under federal law, a factor that federal investigators cited in explaining why no arrest or further enforcement occurred before the attack.
The shooting has renewed debate over how platforms moderate extremist content, how tips to federal authorities are handled and what additional tools or legislation might be necessary to prevent future attacks. Local and federal officials said their inquiries remain active as they assemble a fuller timeline of the shooter’s online activity and possible ties to extremist networks.