The incident occurred at about 9:30 p.m. while people were watching the Joliet Park District's fireworks show at Joliet Memorial Stadium from the nearby parking lot at Jefferson Street and Caterpillar Drive, Roechner said.
Witnesses reported hearing gunshots and glass breaking and seeing a black male, age 16 to 19 and dressed in grey shorts and a white shirt, carrying a gun and running towards Caterpillar Drive, he said.
Police investigators recovered two 9-mm bullet casings but have not found the damaged car, Roechner said. It's not known if anyone was struck; no one was treated at area hospitals for bullet-related injuries, he said.
Anyone with information on the incident is asked to call Joliet police at 815-724-3020 or Crimestoppers of Will County at 800-323-6734.