COLUMBIA, S.C. (AP) — Three more ex-South Carolina law enforcement officers have been sentenced to federal prison following an FBI operation in which agents posed as Mexican drug cartel members.

A U.S. judge in federal court in Columbia sentenced Carolyn Colter Franklin, 64, a former Orangeburg County deputy; Allan Hunter, 52, a former Springfield police officer; and Nathaniel Miller Shazier, III, 29, a former Orangeburg County deputy, on charges of conspiracy to defraud, the U.S. Attorney’s Office for the District of South Carolina announced Monday.

The three are the last of six Orangeburg County officers to be sentenced in the undercover sting, in which prosecutors have alleged the officers thought they were protecting Mexican drug dealers, but were really communicating with FBI agents posing as the cartel members. The operation occurred from December 2018 to March 2019.

FBI wiretaps and videos showed the officers agreed to use patrol cars in uniform and accept payment to “guard” fake truckloads of drugs they were told were traveling through Orangeburg, officials said. Prosecutors said some officers also conspired to create fraudulent documents for nonimmigrants in exchange for bribes.

Franklin received five years and one month in prison, Hunter got five years and three months in prison and Shazier, was sentenced to three years and 10 months in prison. The defendants were all also ordered to complete three years of supervised release.

The Justice Department previously convicted a former Springfield officer and two former Orangeburg County deputies in the case. A security guard has also pleaded guilty to knowing about an illegal scheme and not informing law enforcement. He was set to be sentenced at a later date, according to his attorney.