Authorities Have Determined The Cause Of A Fire That Destroyed A Popular Eating Place In Unicoi County. It Happened Tuesday Night At Clarence’s Drive-In On Unicoi Drive Just Before 11pm. Unicoi County Sheriff Mike Hensley Said The Fire Was Accidental As An Asphalt Sealing Company Used A Propane Burner To Get Rid Of Grass In Cracks On The Asphalt.