Investigation into Aztec High School shooting could take months

• Search warrants were issued for shooter's home and to search computer in his bedroom.
• Shotgun shells, empty boxes of 9mm ammunition and a .22-caliber rifle found in shooter's home.
• Area law enforcement provided support for Aztec police during and following the shooting.

FARMINGTON — The multi-agency investigation into the Aztec High School shooting is progressing, and investigators believe it could take months before the case is wrapped up.

The San Juan County Sheriff's Office, the FBI and the New Mexico State Police are investigating the Dec. 7 shooting where junior Francisco "Paco" Fernandez, 17, and Senior Casey J. Marquez, 17, were shot and killed by a shooter who later killed himself.

The sheriff's office is currently following up on leads, including interviews with witnesses to the shooting, according to Det. Jarrod Slindee.

Some of the search warrants signed and sealed on Dec. 7 by District Judge Sandra Price included requests for information on the students in the 500 and 900 buildings of Aztec High School during the shooting, according to a copy of the warrants. The warrants were unsealed on Dec. 8.

Slindee described the investigation as a unified effort between the three agencies.

"The case will be open for a long while," Slindee said.

MORE: Aztec High School shooter had timeline, deadly plans

A search warrant was approved to search the home of shooter William Atchison on Dec. 7.

Deputies and FBI special agents went to the residence on the 1000 block of Rio Hondo Road following the shooting and made contact with the shooter's mother as they cleared the interior of the house, according to the search warrant.

An inventory of items collected from the home includes a box for a Glock handgun, empty boxes of 9mm ammunition, shotgun shells, a .22-caliber rifle and a metal box with various casings and ammunition in it, according to court documents.

Slindee declined to comment on who the items belonged too.

Also listed were items including a composition notebook with the word "bye" written on it and a copy of the book "Walking in Daniel's Shoes" written by author Tom Mauser.

The book is about Tom Mauser and how he dealt with the death of his son, Daniel Mauser, which occurred during the Columbine High School shooting on April 20, 1999.

MORE: Suspect identified in Aztec High School shooting

The copy of the book in the residence was in scripted to "Bill Atkinson" from the author, according to court documents.

Law enforcement is investigating the online activities of the shooter, who was the focus of an article published online by The Daily Beast about his alleged obsession with school shootings and school shooters along with violent and racist posts he may be linked to on internet forums and websites.

A search warrant to seize and search a desktop computer in the shooter's bedroom and an Xbox 360 gaming console stated the shooter spent a lot of time using his computer and the Xbox 360.

As the investigation into the shooting was underway on Dec. 7, area law enforcement provided support for Aztec police by lending officers to provide a presence in Aztec schools and helped answer calls.

Aztec Police Chief Mike Heal said he spoke to Farmington Police Chief Steve Hebbe and asked for Farmington to station an officer at each of the schools in the Aztec Municipal School District.

It was important for Chief Heal to have the students and staff to feel comfortable and safe at the schools.

MORE: Families reunite after Aztec High School shooting leaves two students, shooter dead

"We offered our officers to be present so Aztec officers could focus on citizen calls," Farmington police spokeswoman Georgette Allen said.

Farmington officers were stationed at Aztec schools on Wednesday and Thursday, Allen said. The sheriff's office also had deputies present in Aztec schools this week, according to Slindee.

The Bloomfield and Farmington police departments provided support on the day of the shooting, but are not involved in the investigation.

Several officers for the Bloomfield Police Department helped answer calls in Aztec on the day of the shooting, according to Bloomfield Police Chief Randy Foster.

Both Bloomfield and Farmington officers were present in schools in the district on the day of the shooting and the day after on Dec. 8.

Officers were staged at Aztec High School on Thursday and Friday as students and families for "Aztec Strong" events designed to help students re-integrate with the school.

There will be a police presence at Aztec high on Monday when students return to class and on Tuesday, Heal said.

Joshua Kellogg covers crime, courts and social issues for The Daily Times. He can be reached at 505-564-4627 or via email at jkellogg@daily-times.com.