Knoxville firefighters responded to a fire at Loveland Baptist Church on Spring Hill Road just before 8 p.m. Sunday night.
When firefighters arrived, they found smoke coming from the eaves of the old sanctuary building.
Crews worked to cut away parts of the roof so they could have ventilation near the area the fire, according to Captain D.J. Corcoran with the Knoxville Fire Department.
As firefighters got the fire under control and began to search for hot spots, a second fire erupted between the roof and interior ceiling of the sanctuary.
No one was inside the church when the fire started. Arson investigators were at the church on Sunday night examining the source of the fire.
A firefighter suffering from heat exhaustion, but is expected to be fine.