BOWLING GREEN, Ky. (WDRB) - The neighbor of U.S. Sen. Rand Paul accused of assaulting the Kentucky Republican while he was mowing his lawn pleaded not guilty at his arraignment in Bowling Green on Thursday.

Rene Boucher and his attorney were at the Warren County Justice Center for Boucher's first court appearance after he was charged with misdemeanor fourth-degree assault. 

Paul and Boucher have been neighbors for 17 years in a gated community, and Boucher is accused of attacking the senator while he mowed his lawn last weekend. 

Paul wrote on Twitter Wednesday that he suffered six broken ribs and a pleural effusion, which is excess fluid around the lungs. The injuries have sidelined Paul from the Senate as he recovers at his home.

The reason for the alleged assault is still unclear. But Paul's senior advisor Doug Stafford tells WDRB that this is a serious criminal matter involving serious injury.

" As to reports of a longstanding dispute with the attacker, the Pauls have had no conversations with him in many years. The first "conversation" with the attacker came after Sen. Paul's ribs were broken. This was not a “fight,” it was a blindside, violent attack by a disturbed person. Anyone claiming otherwise is simply uninformed or seeking media attention," said Stafford.

Earlier this week, Boucher's attorney said it was not about politics. He called it "a very regrettable dispute" that was "trivial."

When asked if the charges against Boucher could be upgraded, the county attorney says the FBI is on the case.

After Thursday's arraignment, Boucher and his attorney left through a side door, dodging the media.

For now, Boucher is facing up to a year in jail. He has been ordered to stay at least a thousand feet away from Paul -- or 200 feet if he's at home. 

Boucher is due back in court Nov. 30. 

Through a spokesperson, Paul declined our request for an interview. 

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