The announcement the billionaire businessman would postpone the rally until another day led a large portion of the crowd inside the University of Illinois at Chicago Pavilion to break out into raucous cheers. Many rushed onto the floor, jumping up and down with their arms up in the air.
"Trump represents everything America is not and everything Chicago is not," said Kamran Siddiqui, 20, a student at the school who was among those celebrating. "We came in here and we wanted to shut this down. Because this is a great city and we don't want to let that person in here."
Some supporters of the Republican front-runne "We want Trump! We want Trump!" in response to the celebrations, and there were some isolated physical confrontations between members of the crowd. Chicago police said they made some arrests.
"It's a shame," said Trump supporter Bill Tail, 43, of the Chicago suburb of Oaklawn. "They scream about tolerance, but are being intolerant themselves. That doesn't make sense."
As Trump attempts to unify a fractured Republican Party ahead of next week's slate of winner-take-all primary elections, the confrontations between his legion of loyal supporters and protesters who accuse him of stoking racial hatred have intensified at his rallies.
A North Carolina man was ar video footage showed him punching an African-American protester being led out of a rally in that state on Wednesday. At that event, Trump recalled a past protester as "a real bad dude."
"He was a rough guy, and he was punching. And we had some people — some rough guys like we have right in here — and they started punching back," Trump said. "It was a beautiful thing."
At Trump's rally earlier Friday in St. Louis, he was repeatedly interrupted by protesters. Police there charged nearly three dozen people with general peace disturbance.
Texas Sen. Ted Cruz, second in delegates to Trump in the GOP race, said late Friday that the billionaire has created "an environment that encourages this sort of nasty discourse."