The cause of Thursday’s fire at a Guelph business was accidental.

Firefighters were called to Nicklin Auto Parts and Recyclers on Eastview Road after flames broke out in the back of the building.

One firefighter was taken to hospital with minor injuries, but is now recovering at home.

Deputy Chief John Osborne says the fire was started by welding materials. They were still warm when someone threw them into a combustible container.

Damage is estimated at $250,000.