A father-son duo of Grundy County deputies face federal civil rights charges for using excessive force on arrestees, authorities announced Wednesday.

A federal grand jury in Chattanooga indicted Grundy County Sheriff's Office Chief Deputy Tony Bean and his son, Sgt. T.J. Bean, in connection to an assault on an arrestee on Dec. 30, 2017.

Both father and son are accused of assaulting the arrestee, who is identified in the indictment only by his initials. T.J. Bean, 29, is accused of assaulting the arrestee while the arrestee was handcuffed, according to the indictment.

Tony Bean, 59, also faces charges he assaulted another arrestee on Aug. 10, 2014, while he was the chief of the Tracy City Police Department.

The father faces four counts of deprivation of rights under color of law, according to the indictment. The son faces one count of the same charge. Each count carries a maximum sentence of 10 years.

Further details of the charges were not available Wednesday evening.

The indictment followed an investigation by the FBI's Knoxville division. In a statement, Grundy County Sheriff Clint Shrum said the investigation lasted for nearly a year.

"The sheriff's office has cooperated with the Department of Justice through the investigation and will continue to do so," Shrum said. "This is certainly not the outcome we expected. Currently, I am considering my options regarding their employment status within the agency."

Attorneys Rebekah Bailey and Kathryn Gilbert of the Justice Department's Civil Rights Division will prosecute the case alongside Perry Piper, assistant U.S. attorney for the Eastern District of Tennessee.