Thousands of students are planning to protest Donald Trump when he comes to the University of Illinois' Chicago campus Friday. And many professors don't want him there either. They worry the scene could turn violent.
More than 300 faculty and staff members have asked the college to cancel the event for the leading Republican presidential candidate, citing reports that his supporters and security have verbally and physically assaulted those opposing the candidate at recent campaign rallies.
"We are deeply distressed that this event threatens to create a hostile and physically dangerous environment to the students, staff, faculty and alumni who come out to express their opposition," the letter reads.
Nearly 50,000 people have signed an online petition against Trump coming to UIC. And more than 9,000 have said on Facebook they'll be there to protest.
The petition says the rally has "no place" on a college campus, because "Donald Trump is running on a platform of hate and dangerous intolerance."
As of Thursday, the rally is still on.
While the university is not endorsing Trump, it's renting out the venue to his campaign -- as it would any other political candidate that requested it, Chancellor Michael Amiridis said in a statement.
UIC boasts that it's one of the most diverse college campuses in the nation. A quarter of its 17,000 undergrads are Hispanic, another quarter is Asian and 8% are black. Nearly half come from families whose income is less than $40,000 a year, according to federal data.
Graduate student Jorge Mena Robles started the petition Friday night after Trump's UIC rally was announced. He's an undocumented student who came to the United States with his parents when he was 8 years old.
"I don't want to see Trump threaten my family and friends on the same stage where I received my bachelor's diploma and will receive my master's in May," Robles told CNNMoney.
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But it's not just about his platforms. It's also the way protesters have been ejected out of recent rallies and treated by Trump supporters that has some people concerned.
"If this were any other presidential candidate with conservative values, like Cruz or Rubio, we would not have written this letter. This is not about free speech, it's about security," said Latin American studies professor Amalia Pallares.
Just last week, the scene at a Trump rally grew intense when more than two dozen protesters chanting "black lives matter" were ejected. They linked arms, resisting the security officers, and some fell to the ground.
Earlier this month, about 30 black students were escorted out by law enforcement at a rally at Valdosta State University in Georgia, though they weren't actively protesting at the time.
Trump himself often calls for protesters to be ejected when they interrupt his speeches, lines usually greeted by applause.
"So if you see somebody getting ready to throw a tomato, knock the crap out of 'em," he once told a crowd.
A 78-year-old man was arrested and charged with assault Thursday after videos posted online appear to show him punching a black protester in the face at a Trump rally in North Carolina.
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The professors say they are concerned about the safety of protesters, as well as staff working the event and students who may be simply walking by the venue. They're worried they could become the targets of verbal attacks from Trump supporters.
"We are a very diverse campus with many undocumented students, and we want to make sure they're protected," Pallares said.
UIC has said that its own police will be responsible for the safety and security of people on campus property. The U.S. Secret Service, Illinois State Police and the Chicago Fire Department will be on site, and the Chicago police will be responsible for the streets around the venue. A parking lot is designated specifically for demonstrations.
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The rally is a private event, so the Trump campaign can say who it does and doesn't let in. A Trump spokeswoman did not respond to a request for comment for this story.
The university says the event will not endanger its core values of freedom and equality.
"We encourage public and civic engagement by all members of our University and we endorse the idea that the answer to speech that one does not like or finds offensive is more speech and not censorship," UIC Chancellor Amiridis said in a statement.
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Those calling to cancel the event say this is more than a free speech issue.
"The question about whether to hold the event here is not about what he's saying as a political candidate, but the tactics at these rallies to shutdown dissent," said professor Jennifer Brier.
"I have seen the footage from recent events, and I'm worried," she said.