The Daily Beast reports that Aztec High School shooter William Edward Atchison, a 21-year-old gas station worker, "lived a prolific life as a white supremacist, pro-Trump meme peddler who was most known for his obsession with school shooters."

Atchison's postings give a glimpse into the bleak life he was living in rural New Mexico, and how the hopelessness he felt gave rise to violent impulses. From The Daily Beast:

“Look, I’m sorry if I’m rude and hateful or anything, but I don’t know what to do. I’ve lived no life for nearly 19 years, most of which was in the miserable ass sun-belt. Did you know new mexico has the fourth highest suicide rate?” Atchison wrote. “Should I escape this dump or deal with it? How can I become polite and make some friends out there in this world?”

The online news website reports that Atchison left violent and racist rants in comment sections and message boards across the Internet, including the white supremacist website The Daily Stormer, the video game website Steam, and YouTube. He took photos of himself pointing guns into his web camera, and his dozens of screen names were often based on racist tropes or past school shooters.

Agents from the FBI visited Atchison last year after an anonymous user reported a post of his asking users where to find an assault rifle for a mass shooting. The agency concluded that Atchison wasn't a threat, and simply liked to troll online. Atchison would eventually carry out a shooting at Aztec High on Dec. 7, killing two students.