Somebody thought it was funny to set fire to a mattress after leaving it sitting on the law of a Whitman College fraternity over the weekend.

A Walla Walla police officer on patrol was driving by the Phi Delta Theta frat house at 715 Estrella Ave when he saw something just a little unusual: a mattress sitting on the front lawn of the building fully engulfed in flames Saturday night.

The mattress, which was fairly close to the building, was put out by the officer using a fire extinguisher, according to the Walla Walla Union Bulletin.

Officials say when the police knocked on the door of the frat house and informed the members inside what had happened, they had no knowledge the mattress was outside or even on fire.

Police concluded it was likely some sort of a prank, but not sure who or why somebody did it.

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