Jefferson Central Fire Chief Carl Anderson said the fire was especially dangerous because of reports that ammunition was kept in the shed and that it was exploding.
Rigby Police notified neighbors by reverse 911.
He said the shed was 12' x 28' and was used as a "man-cave."
The owner had used a gas and diesel mix to re-ignite a fire in a wood stove. The fire ignited vapors outside the stove and traveled into the container the homeowner was using. He dropped the container and the fire quickly spread.
Although the homeowner, who was not identified, stated his fingertips were slightly burned, there were no other injuries.
Damages were estimated at $1,500 to contents and $2,000 to the replacement cost of the shed.