Fentress County Sheriff Chucky Cravens, who resigned last week amid an FBI probe, will face federal charges, as investigators allege that he had sex with inmates.

Information released by the Department of Justice on Thursday indicates that Cravens had inappropriate contact with four different inmates at the Fentress County Jail. Allegedly, Cravens used his position as sheriff to provide additional benefits to three of the inmates in exchange for sexual relationships.

Specifically, the U.S. Attorney’s Office alleges that the sheriff personally transported the inmates from jail to visit relatives, allowed them outside of jail to smoke cigarettes, and provided money to relatives to be deposited in the inmates’ commissary accounts.