Chicago police blocked off all entrances to Rainbow Beach on Friday with law enforcement vehicles and Department of Streets and Sanitation plows in an effort to prevent large gatherings from escalating. This comes as Chicago Mayor Brandon Johnson called on parents and guardians to take steps to prevent what he called "unsanctioned teen gatherings" following reports of planned unauthorized large meetups this weekend. “As we enter the weekend, I am urging parents, guardians and trusted adults to help prevent unsanctioned teen gatherings, know where your children are, and talk with them about the risks of attending these events," Johnson said in a statement issued Friday afternoon, in part. #rainbowbeach #teentakeover #chicagosouthside