According to the Sullivan County Sheriff's Office, the shooting took place at approximately 1 p.m. on the 1500 block of Pleasant Grove Road in Bluff City.
A sheriff's office spokeswoman said deputies arrived at the scene to find an adult male victim in a wooded area suffering from a gunshot wound to the back.
The man was transported to Johnson City Medical Center for treatment. The victim reportedly underwent surgery and is listed in serious condition.
At least one person has been taken into custody in connection with the shooting.
The identities of the shooting victim and the person taken into custody were not immediately available. Authorities also did not reveal the type of firearm used in the incident.
The shooting remains under investigation by SCSO detectives.
Additional information regarding the incident is expected to be released Monday morning, the spokeswoman said.