1 of 5
Charles Rex Arbogast, Associated Press
A Chicago police officer stands his post outside the University of Illinois-Chicago Pavilion, before a rally for Republican presidential candidate Donald Trump Friday, March 11, 2016, in Chicago.

ST. LOUIS — Facing intensifying criticism for the violent clashes between supporters and protesters that have come to define his rallies, GOP presidential front-runner Donald Trump on Friday continued to taunt those who interrupt his events while promising that police and security would be "gentle" as they removed them.

"They're allowed to get up and interrupt us horribly and we have to be very, very gentle," Trump said in response to one of nearly a dozen interruptions as he spoke in St. Louis at the regal Peabody Opera House. "They can swing and hit people, but if we hit them back, it's a terrible, terrible thing, right?"

Throughout his speech, Trump was deeply critical of the protesters, all of whom appeared to leave the venue largely without incident. Police later said that 31 people were arrested and charged with general peace disturbance, and one person was charged outside the venue with third-degree assault.

He panned the protesters as weak "troublemakers," ordered them to "go home to mommy" or "go home and get a job" because "they contribute nothing."

"These are not good people, just so you understand," Trump said. "These are not the people who made our country great. These are the people that are destroying our country."

As Trump attempts to unify a fractured Republican Party, racially charged images of his supporters attacking protesters and allegations that he's inciting violence have cast new attention on the divisive nature of his candidacy.

It intensified this week, when a North Carolina man was arrested after video footage showed him punching an African-American protester being led out of a rally in that state on Wednesday. At the event, the billionaire real estate mogul 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."

Friday's gathering in St. Louis was his first public campaign event since, and Trump defended his conduct and lashed out at the press for making too much of the clashes.

"You know, they talk about a protest or something. They don't talk about what's really happing in these forums and these rooms and these stadiums," Trump said. "They don't talk about the love."

He added that he and his supporters aren't angry people, but they "do get angry when we see the stupidity with which our country is run and how it's being destroyed."

"I'd rather be too strong than too weak, by a long shot," he said.

Trump planned an evening rally later Friday at the University of Illinois at Chicago — a civil and immigrant rights organizing hub with large minority student populations.

Hundreds of people lined up outside the venue hours before Trump's scheduled appearance, separated from an equally large crowd of anti-Trump protesters by a heavy police presence and barricades.

Some Trump supporters walking into the area chanted, "USA! USA!" and "Illegal is illegal." One demonstrator shouted back, "Racist!"

One protester, 64-year-old Dede Rottman of Chicago, carried a placard that read, "Build a Wall Around Trump. I'll Pay for it."

However, 19-year-old Rusty Shackleford of Lombard, in line to attend the Trump rally, said he was there to "support the man who wants to make America great again."

Trump's visit created waves on the campus from the time it was announced. Dozens of UIC faculty and staff petitioned university administrators to cancel the rally, citing concerns it would create a "hostile and physically dangerous environment" for students.

Organizers of a student-led group, who expected hundreds of participants, planned to meet on campus and march to the arena where Trump was to speak and set up shop in a nearby parking lot. Members of Black Lives Matter Chicago, which has held largely peaceful smaller protests following a police-involved shooting in Chicago, also planned to participate.

Colvin reported from Fayetteville, North Carolina. Associated Press writers Sophia Tareen and Sara Burnett in Chicago contributed to this report.

Follow Jill Colvin on Twitter at: http://twitter.com/colvinj