A female Marion County Sheriff's detective was accidentally shot on Wednesday afternoon at the Sheriff's Office at Jasper.
The detective was rushed to a Chattanooga hospital.
Marion County Sheriff Bo Burnette said the detective was shot in the leg. He said the leg was broken and a pin will be inserted. He said she was undergoing surgery and may have additional surgery on Thursday.
He said it involved "two detectives who had worked together for five years and were like brother and sister. One would never do anything to harm the other.
"He's a total wreck. It's a bad, bad situation."
A large number of officers were at the hospital in the wake of the incident. They provided a convoy to the hospital.
The TBI is investigating the incident.