A former U.S. Postal Service letter carrier in Utah was indicted for allegedly discarding more than 300 mail-in ballots intended for voters ahead of the state's June primary election.

Damon Matai Seei, 34, of Payson, was arrested Tuesday morning and appeared in federal court in Salt Lake City, where he pleaded not guilty to one count of unlawful secretion, destruction, and delay of mail. A federal grand jury indicted him on September 16, and the charges were unsealed Tuesday.

Prosecutors said Seei was delivering mail on June 3 in Eagle Mountain when he separated the ballots from other items shortly after starting his shift. He allegedly drove to a church parking lot not on his route and threw the ballots and additional mail into a dumpster about 90 minutes later. Voters later complained to the Utah County Clerk after failing to receive their ballots, and officials determined that roughly 304 registered voters in one district never got theirs.

U.S. Attorney Melissa Holyoak said Seei told investigators he acted out of frustration and laziness to reduce his workload, with no political motive. Acting Deputy Attorney General Trent McCotter described the actions as a serious federal crime that undermines election integrity.

Seei is no longer employed by the Postal Service. The investigation continues, and his next court appearance is scheduled for November 30. Officials noted that Utah voters rely heavily on mail ballots, with about 95 percent casting votes that way in recent elections.