An Arizona man who planned to commit a mass shooting at an Atlanta rap concert as a way of inciting a “race war” has been indicted by a federal grand jury on hate crime and firearm charges.

The man, Mark Adams Prieto, hatched a plan in several discussions with two people working with the F.B.I. who posed as racist extremists to carry out a mass shooting targeting Black people and other people of color at a concert in Atlanta on May 14 and May 15, the Justice Department said on Tuesday.

Mr. Prieto intended for the shooting to incite a “race war” before the presidential election, prosecutors said in a news release.

Mr. Prieto, 58, was reported to the authorities last year by an acquaintance who said he had made concerning comments calling for mass shootings targeting Black people and others, according to officials.

Mr. Prieto faces two counts of trafficking in firearms, one count of transfer of a firearm for use in a hate crime and one count of possessing an unregistered firearm.

He faces a maximum 15-year prison sentence for each firearm trafficking and transfer charge and a maximum 10-year sentence for the unregistered firearm charge, prosecutors said. Mr. Prieto also could be fined $250,000 for each count.