The Kentucky doctor who allegedly attacked Sen. Rand Paul, leaving him with six broken ribs, pleaded not guilty to fourth-degree assault charges Thursday.

ABC News reports Rene Boucher, 59, Paul's next-door neighbor for 17 years, tackled the senator to the ground last Friday, according to his arrest warrant.

Since Paul is a member of Congress, U.S. Capitol Police and the FBI assisted in the investigation of the incident, according to ABC News.

Paul tweeted about his injuries Wednesday,

I appreciate all of the support from everyone. A medical update: final report indicates six broken ribs & new X-ray shows a pleural effusion

— Senator Rand Paul (@RandPaul) November 8, 2017

Boucher's attorney claimed Thursday in an interview with ABC News that the incident did, in fact, start as a landscaping dispute and that Paul was not "blindsided" by his client.

He added that claims the encounter was politically motivated were incorrect and that he received a letter from the senator's attorney that Paul intends to sue.