A federal grand jury has indicted an Arizona gun vendor for allegedly selling firearms to be used in a mass shooting he was planning in hopes of inciting a “race war” ahead of the 2024 presidential election, authorities said.
Mark Adams Prieto, 58, of Prescott was indicted Tuesday on charges of firearms trafficking, transfer of a firearm for use in a hate crime and possession of an unregistered firearm, the U.S. attorney’s office in Arizona announced.
Prieto was taken into custody in New Mexico on May 14 after allegedly supplying rifles to an informant and an undercover agent while plotting out an attack on African Americans and other minorities at a concert in Atlanta.
According to federal prosecutors, Prieto told the individuals, who he met while selling at gun shows, that he hoped to “kill as many people as possible” and leave Confederate flags, Ku Klux Klan propaganda and other “offensive rhetoric” at the scene of the shooting in order to incite retaliation and start a race war.
“In his mind, it had to unequivocally be perceived as race related. He expressed frustration with the direction the country is going and a willingness to do violence to change its direction,” prosecutors said in a May 17 court document arguing for his detention pending trial.
Prieto allegedly personally chose the city where the shooting would take place and the specific guns that the trio would use in their attack. When one of the other two participants said they did not have an AR-15 rifle, which was the firearm Prieto wanted everyone to use, Prieto supplied them with one, prosecutors said.
“Prieto did not know the individuals were working with the government, but instead believed that they shared his racist beliefs and wanted to commit a mass shooting to incite a race war,” the U.S. attorney’s office in Arizona said in a statement announcing his indictment.
Prieto was ultimately arrested while driving east from Arizona through New Mexico. In his vehicle authorities said they found seven firearms, which he said he was taking to a gun show in Florida where his mother lives. The government agent and informant said Prieto told them he was heading to Atlanta to do reconnaissance. The concert selected for the attack was scheduled to run from May 14-15.
Authorities searched his Prescott home, which he shared with an elderly man, and recovered approximately 178 firearms. These included some suspected automatic firearms and short-barreled rifles, which are illegal to possess without proper registration, prosecutors said.
In an interview with federal agents, Prieto admitted to planning a mass casualty event in Atlanta but said that it was only a “fantasy” and something he never would have actually done. He said he planned to call it all off when he regrouped with the two individuals at a gun show in June, authorities said.
Prieto’s defense attorney, in requesting his pre-trial release last month, argued that the federal government had not presented adequate proof that his plot wasn’t more than fantasy or that he is a flight risk or danger to the public. His alleged racist beliefs, “even if true,” also should not be a basis for denying him bail, they added.
A judge disagreed and ordered Prieto to remain jailed, citing the “strong” weight of the evidence against him and the lengthy prison sentence he faces if convicted.
Each conviction for firearms trafficking and transfer of a firearm for use in a hate crime carries a maximum penalty of 15 years in prison. A conviction for possession of an unregistered firearm carries a maximum penalty of 10 years in prison, the U.S. attorney’s office said.
Prieto’s attorney did not immediately respond to a request for comment Thursday.