SPRINGFIELD, Ill. — A 65-year-old Army veteran pleaded guilty Friday to making a threat against a Republican congressman from Illinois.

Randall E. Tarr, of Rochester, Illinois, left a profanity-filled voicemail at U.S. Rep. Rodney Davis' office in Decatur on Nov. 25 threatening to shoot him, federal prosecutors said.

The voicemail was forwarded to the U.S. Capitol Police, who used caller ID to determine that Tarr had left the message, according to court documents.

Tarr told The Associated Press in December that he saw a television ad in which Davis, a Republican from Taylorville, claimed that Ukraine, not Russia, was responsible for meddling in the 2016 U.S. elections, and it angered him enough to call.

"I said I had been a sharpshooter in the Army. I didn't realize I said anything about shooting him. I might have. I don't even own a weapon," Tarr said. "I wish I could just take it all back and just say he's a lousy (expletive) for backing the Russian theory."

Tarr is scheduled to be sentenced on Nov. 20. The crime of making a threat to a federal official carries a maximum penalty of 10 years in prison.

Davis was practicing with the congressional baseball team Alexandria, Virginia, on June 24, 2017, when a man from Illinois opened fire on the players, seriously wounding House Majority Whip Steve Scalise of Louisiana and three other people.