(CNN) Law enforcement authorities are searching for a man who's suspected of threatening to shoot President Donald Trump.

Shawn Richard Christy, of McAdoo, Pennsylvania, was last seen in Cumberland, Maryland, Sunday night driving a stolen vehicle, according to the authorities.

The US Marshals Service is offering $20,000 for information leading to Christy's arrest. Christy has been wanted on a June 19 federal warrant, accused of posting threats on Facebook against the President and Northampton County District Attorney John Morganelli.

According to officials, Christy posted, "Keep it up Morganelli, I promise I'll put a bullet in your head as soon as I put one in the head of President Donald J. Trump."

Christy is a 27-year-old white man who stands at 5 feet 10 inches and weighs about 160 pounds, according to a flyer released by the FBI. He has short dark blond hair, a large tattoo on his right upper arm of a "pointed cross and barbed wire," and speaks with a distinct lisp.

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