A Donald TrumpDonald John TrumpRed states find there’s no free pass on Medicaid changes from Trump Trump meets with Moon in crucial moment for Korea summit The Memo: Trump flirts with constitutional crisis MORE rally that was scheduled for Friday night in Chicago was indefinitely postponed over security concerns after hundreds gathered outside the UIC pavilion to protest the GOP front-runner's event.

A Trump rally earlier Friday in St. Louis, Mo., resulted in dozens of arrests amid reported scuffles between protesters and Trump supporters.