Donald Trump is on edge.

During a rally in Dayton, Ohio, on Saturday, the Republican presidential frontrunner was standing in front of a jet bearing his name and in front of a crowd shouting the same. All of a sudden, a protestor reportedly shouted something behind him, causing Trump to wheel around in shock, and security to run on stage. The moment was a jarring one:

That being said, it’s a far cry from the violence faced by protesters—even by members of the press—at these same rallies. Last night in Chicago, while one BlackLivesMatter protestor was bleeding from his head, a CBS News reporter was arrested and pinned down by a policeman’s boot.

Trump has said that his supporters should feel free to “knock the crap out of” protestors at his events. But as he learned today, turning a campaign event into a WWF-style all-out battle royal comes with its drawbacks.

Update: Another angle of the incident shows a man rushing the stage, jumping a barrier before he was headed off by security.

Contact the author at melissa.cronin@gawker.com.