Suspect identified in Aztec High School shooting

AZTEC — Police say Aztec resident William Atchison, 21, disguised himself as a student and entered Aztec High School Thursday morning with the intention of holding a class hostage, killing students and then killing himself.

The thumb drive Investigators found on Atchison's body, contained a note detailing his plan. Police also found a schedule torn up in a trash can at his house that included his plan to die at 8 a.m. that morning.

MORE: 2 students killed, shooter dead after Aztec High School shooting

Atchison's only interaction with police in the past was in March 2016 when someone reported a message he wrote on an online gaming site asking where to acquire cheap assault rifles for a mass shooting. The FBI did not find any evidence of a crime being committed and ended the investigation. Police say Atchison claimed he had made the post as an internet troll.

“William Atchison, 21, he was a single coward shooter,” said San Juan County Sheriff Ken Christesen. “This was a planned event. The gun he used was a Glock pistol that he purchased locally and legally.”

MORE: Investigators: Aztec High School shooter had timeline, deadly plans

Christesen said the shooter had a clean criminal record, not even a parking ticket.

“This person is not only a coward, he’s evil. It’s just a shame that he wasn’t on our radar,” Christesen said.

He did not have any weapons in 2016, and purchased the pistol he used in the shooting last month, according to police.

Francisco "Paco" Fernandez was shot when he walked into the bathroom where Atchison was getting ready for the shooting. Casey Marquez was killed in a hallway. The school then went into lockdown. Atchison shot at people who were hiding in a storage closet, but none of them were hit by the bullets, according to police.

Police say neither victim was targeted.

Hannah Grover covers government for The Daily Times. She can be reached at 505-564-4652 or via email at hgrover@daily-times.com.

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