According to police reports, Jahn had practiced target shooting with his father at their property in Durant, Oklahoma, about a month before the deadly rampage. His father was reportedly surprised when Jahn revealed he had purchased an “old rifle” online. Authorities later confirmed the weapon used in the attack had been legally obtained.
The records portray Jahn as a reclusive, unemployed man “obsessed with artificial intelligence” and detached from social life. His parents described him as a loner who rarely spoke but occasionally discussed current events with his mother. He had no history of mental health treatment, they told investigators.
Jahn’s online activity also reflected his isolation. Analysts with the Institute for Strategic Dialogue said he logged more than 11,000 hours on first-person shooter and survival games under the username “Frank Hoenniker,” a reference to a character from Kurt Vonnegut’s Cat’s Cradle.
Photos from the scene showed Jahn’s car adorned with a map depicting radioactive fallout zones in the U.S.—a chilling nod to his fixation on radiation exposure, which he reportedly linked to his time working at a marijuana farm in Washington near sites once used for atomic research.
Authorities continue to review Jahn’s writings and digital history, but investigators say there is no indication that he was part of any organized extremist group.