A semi was destroyed by a large fire at the Route 33 westbound rest area Monday morning around 9:15.
The Bellefontaine Fire Department said the cab was fully engulfed when they arrived.
Sean Hoffman, 25, of Marysville, stopped to use the restroom.
Moments later, Hoffman heard a whoosh sound and saw smoke under the cab.
Firefighters prevented the blaze from reaching the trailer.
The fire caused about $40,000 worth of damage.
No one was injured.
The Marysville Post of the State Highway Patrol assisted at the scene.
Troopers report that the rig is owned by Greyhound Hauling Express from Marysville.