A grass fire spread by gusting winds was the cause of a blaze that leveled a 2 1/2-acre warehouse Tuesday afternoon, officials said Wednesday night.

Midvale Fire Chief Merrill Ross said investigators from the Salt Lake County Arson Task Force and state fire marshal's office found evidence that a small patch of grass on the south side of the warehouse at 7150 S. State had been burning before the warehouse became engulfed in flames Tuesday afternoon. Wind spread the fire about 4 feet to the plywood wall of the warehouse several hundred feet from the roadway, Ross said."We have not found any evidence that would lead us to believe it was arson," Ross said.

Investigators have no clues about how the grass was ignited, but have not ruled out human involvement. Ross said information gathered by investigators, including pictures taken of bystanders, will be investigated.

The fire caused $250,000 damage to the warehouse, which was used by Allied Development Co. to store Christmas trees.