A South Wenatchee business in was damaged by fire early Tuesday morning.

The blaze broke out just before 6:15 in the 700 block of South Worthen Street at Shepherd's Oil.

Deputy Chief Andy Davidson with the Wenatchee Valley Fire Department says the fire started outside the business' main building.

"It was originally toned out as a brush fire but was upgraded to a commercial structure fire. It looks like the fire started in an outhouse behind the storage buildings at Shepherd's Oil."

Crews were on scene within minutes and quickly knocked down the flames but not before they spread to a part of Shepherd's primary shop building, where it caused minor damage.

Davidson says investigators are still working the scene.

"It is unknown if this might be arson or was accidental and it's under investigation."

Shepherd's Oil has several large fuel tanks on the premises, but Davidson says those were not compromised by the fire.

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