A storage shed at a Rochester High School was wiped out by a fire Monday afternoon.

Deputy Fire Chief Steven Belau says a passerby reported the fire at John Marshall High School around 3:50 p.m. and directed firefighters to a small building on the north side of the school at 1510 14th Street Northwest. The outbuilding, which was used to store pottery kilns, was already engulfed in flames when they arrived.

It proved to be a dangerous situation because of gas escaping from the LP cylinders used to fuel the kilns. A portion of the school was evacuated and a section of 14th Street was closed off while firefighters worked to cool the tanks with water to prevent an explosion.

The cause of the fire remains under investigation.

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