Kentucky Senator Rand Paul suffered five broken ribs and bruises to his lungs in an assault by a neighbor at his home in Bowling Green, Kentucky on Friday (3 November). Police and an aide to Paul said on Sunday that his injuries were more severe than initially thought.

Kentucky State Police said they have charged the neighbour, identified as Rene Boucher, 59, with one count of fourth-degree assault in the incident. He was later released on $7,500 bail.

Police added that Boucher, a practising anesthesiologist, admitted to have tackled the Republican senator at his home on Friday evening around 3:20pm local time (8.20pm UK time). It was not clear if the attack was politically motivated. It was found that Boucher was registered as a Democrat, according to voter records of March, USA Today reports.

In his criminal complaint, Paul reportedly told police that his neighbor "came onto his property and tackled him from behind, forcing him to the ground and causing pain".

"Senator Paul was blindsided and the victim of an assault," stated an email from a spokeswoman for Paul's office, confirming the incident. "The assailant was arrested and it is now a matter for the police. Senator Paul is fine."

Doug Stafford, a senior adviser, said on Sunday night that Paul's rib injuries included three displaced fractures. "It is not clear exactly how soon he will return to work, as the pain is considerable, as is the difficulty in getting around, including flying," Stafford added.

A neighbor of Paul reportedly told NBC affiliate WAVE of Louisville that the two men have had ongoing problems. The person added that Paul was mowing the lawn at the time of the assault.

The FBI was at the scene following Paul's complaint and was investigating the incident. David Habich, a spokesman for the FBI, said: "We are working with our state and local partners to determine if there was a violation of federal law."

Attacking a senator is a federal crime and Boucher could face serious legal implications. It was not clear if he has an attorney.