... It might have served as a warning to some, as another “teen takeover” unfolded in the heart of downtown the following night, and two teen boys were shot and wounded near Millennium Park. More than a dozen police reports obtained by the Tribune show how the chaos unfolded as Chicago police for hours struggled to control hundreds of teens and young adults as they darted through traffic, smashed windows and carried out acts of violence. Large outdoor gatherings of young people aren’t new in Chicago, and the “teen takeover” events — organized on social media, usually a few days...