AZTEC - A 21-year-old gunman who disguised himself as a student to get into a New Mexico high school where he killed two students had caught the attention of U.S. investigators more than a year ago, authorities said Friday.
William Atchison, a former student at small-town Aztec High School, had legally purchased a handgun at a local store a month ago and planned the attack, authorities said. He left a message on a thumb drive found on his body that detailed his plan to wait until the students got off buses and made their way to class.
He walked into the school with them and went into a second-floor bathroom to "gear up." Atchison's plan was to shoot up a classroom and then kill himself.
"Work sucks, school sucks, life sucks. I just want out of this (expletive)," he wrote.
More lives could have been lost had Francisco I. Fernandez not walked into the bathroom, authorities said. That's when the gunman shot Fernandez. Atchison walked out into the hallway and encountered the second victim, Casey J. Marquez, and killed her.
The gunman then walked up and down the hall, firing randomly, before killing himself, authorities said.
"This is an act of cowardice," San Juan County Sheriff Ken Christesen said.
Authorities said the shooter did not have a criminal record, much less a traffic ticket. The only contact with law enforcement was what they described as a generic message on an online gaming forum in 2016 in which he talked about what weapons might be used in a mass shooting.
The FBI said the posting was flagged and investigators talked with the gunman at his home in Aztec, where he lives with his parents. At the time, he did not own any weapons other than an airsoft pellet gun and said he had no plans for an attack and just liked to troll sites online.
Christesen said Atchison had legally purchased a 9mm Glock pistol a month ago.
State Police Chief Pete Kassetas says the shooter had multiple magazines with him.
The shooting has rocked Aztec, a town of about 6,500. Hundreds gathered for prayer services and candlelight vigils and more gatherings are planned over the weekend as residents look for answers.
Kassetas said the two victims were not specific targets. Marquez was a cheerleader and student leader at school.
Bryn Divine, a senior at Aztec High School, remembered the victim being a vibrant and friendly student who often won dance contests at school events.
"She lit up pretty much any room we were all in," Divine said. "She was such a fun person to be around."
Fernandez was known for his speedy typing and interest in computers. His family has said he had a bright future ahead of him.
New Mexico Gov. Susana Martinez said she has met with the teens' families and they talked about what great kids they were. Both of them also had jobs.
Martinez said the families are broken but are pulling together.
"I don't think anyone ever gets over this," she said.
Associated Press writers Mary Hudetz and Susan Montoya Bryan contributed to this report from Albuquerque.