Nearly half of the 3% of campus protests that Acled categorized as violent became so because of demonstrators fighting with the police sent in to clear protest encampments. That included incidents at the University of Texas, Austin, on 24 April; at Emerson College in Boston on 25 April; at the University of Illinois, Urbana-Champaign, on 26 April; at Washington University in St Louis on 27 April, when campus officials said that three police officers were injured, including one who had a “severe concussion” and another who broke a finger; and at the University of Wisconsin, Madison, on 1 May, when a state trooper was reportedly injured after being hit on the head with a skateboard.