(KTXL) — An internal investigation of a San Joaquin County Correctional Officer has prompted their arrest on Wednesday, according to the San Joaquin County Sheriff’s Office.

In a private press conference on Thursday, San Joaquin County Sheriff Patrick Withrow named Brandon Wolff as the correctional officer that had been arrested.

Wolff is facing charges of possessing a controlled substance with intent to sell, illegally possessing an assault weapon and possessing marijuana with the intent to sell, according to the sheriff’s office.

“Once we caught wind of any wrongdoing we acted with swift and appropriate measures to remove this cancer from our office,” Withrow said.

Withrow said that three additional county employees, including two correctional officers and a civilian staff member, have been placed on administrative leave.

Their connection with Wolff’s arrest has yet to be confirmed or not by the sheriff’s office, according to Withrow.

Internal investigations are ongoing and Withrow said that if any evidence of criminal activity “this will be brought to the district attorney’s office immediately.”