(WBIR) Forestry Officials said the fire in Caryville is suspected to be arson.
Crews were fighting the fire overnight until around 1 a.m. and were back later Sunday morning.
According to the Tennessee Division of Forestry, the fire has covered about 250 acres and could spread depending on the conditions Sunday, but it appeared nearby homes were not under threat.
Crews were working on what they call "back firing." That's a tactic used to prevent a future fire by lighting property that has not yet burned on fire intentionally.
"We light the area between the fire and the crews to make a controlled fire, so that it doesn't catch on fire in the future. The dry conditions could cause it to go up and so we want to prevent that," said Nathan Waters, Assistant District Forester.
Waters said the area is popular for hikers and climbers, and crews are asking local residents to report any suspicious activity.