Police on Monday announced they had captured a person of interest associated with a shooting that killed six people and wounded more than 36 when a man with a high-powered rifle opened fire from a rooftop at a Fourth of July parade in the Chicago suburb of Highland Park.

Police confirmed they captured 22-year-old Robert E. Crimo III, who was from the area. They said he was driving a silver 2010 Honda Fit automobile.

The shooting caused toddlers to abandon tricycles and parents to run for safety with their children, turning a civic display of patriotism into a scene of panicked mayhem.