A grand jury has indicted Jeffrey Kelly, 60, with one count of terrorism, three counts of discharge of a firearm at a structure, three counts of unlawful discharge of a firearm, and one count of criminal damage. He was arrested after his alleged involvement with multiple shootings at an Arizona campaign office and a separate scare involving a mysterious white substance.

“Kelly first used a CO2 powered gun, then escalated to firearms for the second and third shootings. Over the course of the three shootings, Kelly fired more than twenty times, causing damage to the building’s windows, front doors, and walls,” the Maricopa County Attorney’s Office said in a news release.

Prosecutors said they believe Kelly poses an extreme threat. When law enforcement searched Kelly’s home, they found more than 120 guns and over 250,000 rounds of ammunition, which led law enforcement to believe he may have been planning a mass casualty event. 

“It’s the state’s belief that Mr. Kelly poses the most extreme danger within a democracy and within our community. Trying to disrupt political activity, aiming violence at a political party is completely, completely out of bounds,” the prosecutor told the judge at a court hearing.

The shootings at the Democratic National Committee office in Tempe, Arizona, occurred Monday, Sept. 16, Monday, Sept. 23, and Sunday, Oct. 6. All three shootings happened overnight, between midnight and 1 a.m., and nobody was injured, according to police.

Police also linked Kelly with a suspicious white substance found on anti-Democratic signs in Ahwatukee, Arizona, last week. Suspicious bags of white powder were found hanging from several political signs lined with razor blades. According to AZ Family, the signs with the suspicious bagged powder were critical of the Democratic Party reading, “DEMS LIE” and “DEMS KILL JEWS.”

The signs were removed by authorities upon being found.