The car's driver, who was participating in the parade, apparently suffered a medical emergency, Damascus police chief William H. Nunley said.
Nine people were transported to hospitals, but none had life-threatening injuries, The Washington Post reported.
The car had been traveling at 20-25 miles per hour when it ran into the crowd, sending people running and screaming.
Damascus Town Council member Peg Ayers said there was some "immediate panic," but first responders were quick to help the injured.
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