More than 50 firefighters responded to battle the blaze that broke out early Thursday morning at the Westside Party Rentals at 200 S. 13th Ave.
"It's been a long two days," Stevenson said.
The building had a concrete roof that prevented firefighters from entering from the top, and all entryways were locked. Firefighters were forced to open multiple loading dock doors to help battle the blaze.
All of the contents of the building, which included party tents, chairs, tables and other items, were lost to the fire, Stevenson said. The building itself, which is all concrete, remains intact.
The fire has been ruled accidental.
"We traced the origin to a garbage can in the back of the building that had oily rags," he said. "We aren't sure if it was spontaneous combustion or if it was a cigarette or other item."
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