A Donald Trump rally in Chicago has been canceled for “safety reasons.”

In an unprecedented move for the campaign, Trump has announced he is canceling a rally in Chicago after clashes between supporters and protesters broke out at a planned event at the University of Illinois at Chicago Pavilion. 

The scene at the rally was widely described as “chaotic,” as protesters blocked the streets and made a strong showing inside the building. While reports indicate that police escorted some out, there have also been reports of fights breaking out between supporters and protesters. While Trump rallies have been marked with protests for months, this is the largest disturbance yet, and is surely a sign of things to come, as Trump secures the Republican nomination.