FREDERICKSBURG, Va. (CBSDC/AP) — The National Weather Service says a severe storm in Spotsylvania County that destroyed a gymnasium was a microburst.

Seven people inside the Cheer Fusion gym in Fredericksburg were injured when the storm tore through the Four-Mile Fork area Sunday evening. Media outlets report that two people remain hospitalized.

The storm tore the building’s roof off and collapsed the cinder block walls. Strong winds and falling trees damaged several other homes and buildings.

The weather service says winds reached up to 80 miles per hour.

It describes a microburst as a downdraft in a thunderstorm that is less than 2.5 miles in scale, which can cause comparable or worse damage than tornadoes  with speeds up to 150 miles per hour.

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