Suspect in shooting incidents at Harris campaign office in Arizona was preparing for a ‘mass casualty,' prosecutor says

A 60-year-old man suspected of shooting at a Democratic National Committee office over the last two months and hanging suspicious bags of white powder from politico signs in a nearby village had over 120 guns and over 250,000 rounds of ammunition in his home in preparation for a "mass casualty," according to prosecutors.

The suspect, identified as Jeffrey Michael Kelly, was arrested late Tuesday. He is facing charges that include the unlawful discharge of a firearm, shooting at a non-residential structure and committing an act of terrorism, and misdemeanor criminal damage.

Police said on Wednesday that additional charges may be filed in connection with plastic bags containing a white powdery substance hung on politico signs that Kelly allegedly posted and lined with razor blades in the village of Ahwatukee, Arizona where he lives.

When he was arrested, Kelly had a machine gun and "numerous guns in his car to potentially do something," said deputy county attorney Neha Bhatia.

"The state and law enforcement believes that this person was preparing to commit an act of mass casualty with the guns he had," Bhatia said at Kelly's initial court appearance, noting that investigators also found multiple machine guns, loaded firearms, silencers, long-range scopes and body armor in his home.

Bhatia asked for a $1 million cash bond. Ultimately, Judge William Cawthorn settled on a $500,000 cash bond.

Asked why the county thought he was planning to commit an act of mass casualty, Maricopa County Attorney Rachel Mitchell said, “Without going into further detail into what we found, obviously, that type of those numbers of guns, as well as those numbers of rounds are certainly a factor that you would consider.” 

Police responded three times in three weeks to shots that were fired at the DNC office which organizes and campaigns for Vice President Kamala Harris. The space is shared by staff from Harris’ campaign, staff for the state Democratic Party and campaigns for House and Senate candidates.

Police said the office's front doors and windows were hit by a pellet or BB gun on Sept. 16, and that real bullets were fired at the office a week later, on Sept. 23. Additional bullets were fired at the office in a third incident on Oct. 6.

“We are grateful for the work of the Tempe Police Department and will continue to cooperate with investigators,” Sean McEnerney, the coordinated campaign manager for the Arizona Democratic Party, said in a statement.

Jason Squires, an attorney for Kelly, described him as a retired aerospace engineer and “a sportsman” who had licenses to properly possess a variety of firearms, including a "top secret clearance through his employer" until 2020.

"To kind of guess guilty at this stage is somewhat dangerous for a man who has absolutely no prior anything," Squires said in court.

Prosecutors said that in addition to the firearms, a search of Kelly’s home had turned up two license plates matching those captured in camera footage from two of the offenses, and that camera footage also showed a Toyota Highlander leaving the site where the offenses were committed that matched one found in Kelly’s garage.

Tempe police chief Kenneth McCoy said during a news conference on Wednesday that coordination with silent witnesses following the third incident had helped identify Kelly as the suspect. Community members remembered Kelly from a 2022 incident where he was accused of stealing Democratic campaign signs using the same vehicle that was tied to the recent incidents, McCoy said.

McCoy also acknowledged the threat of political violence with just 13 days leading up to the general election.

"Arizona is in the national spotlight right now. All eyes are on us," McCoy said.

"I want to speak directly to those who would consider using political violence or intimidation to disrupt our upcoming election, we will hold you accountable and use every resource available to us to bring you to justice," he added.

Arizona is one of the critical battleground states that both Harris and former President Donald Trump are vying to win in the election.

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