Arizona investigators surveilling the man accused of shooting at the Democratic National Committee office in a suburb of Phoenix saw him posting political signs with bags of a white, powdery substance attached,

TEMPE, Ariz. — 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 political signs in a nearby village had over 120 guns and over 250,000 rounds of ammunition in his home and was preparing for a "mass casualty" act, according to prosecutors.

Jeffrey Michael Kelly, 60, was also arrested on suspicion of leaving white powder on political signs in Ahwatukee, according to Tempe police.

Jeffrey Michael Kelly was arrested Tuesday and charged with 10 counts including committing a terrorist act. The FBI was searching his home on Wednesday.

Tempe police said Jeffrey Michael Kelly, 60, also is accused of hanging several political ... fired BB pellets and then gunshots at the glass front door and a window of the Arizona Democrats' field office in the early morning hours of Sept.

Tempe (Ariz) police arrested Jeffrey Michael Kelly on Tuesday for allegedly shooting at a Democratic Party office in Tempe and leaving bags filled with white powder on political signs.

Jeffrey Michael Kelly, 60, allegedly fired gunshots at the glass front door and a window of an Arizona Democrats' field office.

Police found a huge stash of guns and ammunition in his home, leading prosecutors to believe he was was planning a "mass casualty" event.

Authorities in Arizona say a man arrested in shootings targeting Democratic campaign offices near Phoenix had more than 120 guns and apparently had been plotting a mass casualty event.