As Trump's supporters filed out of the David L. Lawrence Convention Center at the end of the rally, the two sides engaged in heated verbal confrontations, with supporters chanting "USA!" and "Build that wall!" and protesters shouting profanities. Police in riot gear separated the sides.
According to police, masked protesters, who were trying to reach Trump supporters, pepper-sprayed officers. During the scuffle, one officer suffered a hand injury. Police also said several protesters tried to hit them with sticks they had broken off from signs.
Four officers were treated at the scene for minor injuries.
“I'm very proud of the effort the Pittsburgh Bureau of Police put forward,” Pittsburgh Mayor Bill Peduto said. “There was a good game plan going in, but just like any team sport, a good game plan is only carried out if you have the men and women who are professional and can also show the patience.”
Officers arrested 31-year-old Kennon Hooper, of West Oakland, 27-year-old Lisa Cuyler of Polish Hill and 29-year-old Maxwell Yearick of Perry South.
Police said Hooper kicked two officers after they had been pepper-sprayed by protesters. While he was being handcuffed, Cuyler allegedly jumped on an officer's back.
In Yearick’s case, he tried to fight an officer who has just been pepper-sprayed, according to investigators.
Hooper, Cuyler and Yearick face riot and aggravated assault charges. Hooper and Yearick are also charged with resisting arrest.
Hooper and Yearick remained in the Allegheny County jail Thursday, unable to post bail.
Video shot by a protester apparently shows a local newspaper reporter being shoved by a police officer. Pittsburgh Tribune-Review reporter Megan Guza tweeted that the protester forwarded her the video, and Mayor Bill Peduto responded by saying that authorities are reviewing the video.
Peduto also said that police Chief Cameron McLay would call Guza on Thursday morning.
Guza later tweeted that she was OK, saying, "I'm not the story" and that she has great interactions with police every day.
Meanwhile, inside the convention center, Trump gave a warm welcome and spoke directly about the Steel City’s manufacturing industry.
“We’re going to bring back coal and steel. (We’re) going to bring it all back,” he said.
Trump touched on immigration as well as the trade deficit with China, telling the crowd they should be angry at their leaders for being "so stupid.”
He also mentioned Pittsburgh Steelers quarterback Ben Roethlisberger, saying they’re great friends, and brought up Penn State and Joe Paterno, saying he has a special relationship to Pennsylvania and wants to keep that going.
Ahead of his rally downtown, Trump stopped at Soldiers and Sailors Memorial Hall in Oakland for a one-hour taping with Fox News’ Sean Hannity that began at 5:30 p.m. Dozens of Trump supporters, including some who began lining up for the event at 6 a.m., were turned away from entering.
In anticipation of the increased traffic in Oakland, Dr. Kathy Humphrey, senior vice chancellor for engagement and chief of staff at the University of Pittsburgh, sent an email to faculty and staff Tuesday night. Her email warned about a group that had expressed intentions to openly carry firearms in a demonstration of its commitment to the Second Amendment.
The demonstration Humphrey alluded to in her email was talked about in a post circulating on social media Tuesday night, which encouraged people to openly carry in support of Trump. The message claimed about 50 people signed up to participate, with an additional 16 who would rove around and help avoid roadblocks from counter protesters. However, no one showed up for the demonstration.
At one point in the afternoon, a small group of protesters clashed with supporters near the entrance to the Soldiers and Sailors Memorial Hall.
“Trump might be a little harsh with his words. He may be a little off sometimes, but I think he'll do what he says,” Jeff Duranko, a Trump supporter, said.
Following Trump’s first appearance, a group of protestors marched down Fifth Avenue from Oakland to the David L. Lawrence Convention Center, where Trump held his public rally. Prior to the arrests outside the convention center during Trump’s speech, protesters and supporters clashed while waiting to get inside the facility.
“I believe Trump is trying to set our country back 50 years, and we've done all this work for people of color, of different races and religions, and to go back 50 years is absolutely unacceptable,” Trump protester Taylor Rossi said.
Those who protested publicly against Trump Wednesday included Pennsylvania Democratic U.S. Senate candidate and Braddock Mayor John Fetterman, who held a formal anti-Trump rally in the Strip District around 4 p.m. He encouraged his supporters to "protest Trump's disgraceful and un-American stance on immigration and human rights in this country."
“His particular version of hate is worse because I don’t think he believes in it, just saying what he knows is going to rile up his crowd,” Trump protestor Edward Bates said.
Fifty-eight Pittsburgh police officers were on duty, with another 20 officers from Allegheny County providing assistance. Pennsylvania state troopers also helped.
Since Trump’s rally was held inside the convention center -- a private venue -- the responsibility of keeping crowds outside under control fell on the city.
“That is paid for 100 percent by the city of Pittsburgh,” Peduto said. “It's one of the things about a democracy and the candidates having the ability to speak to the public. That cost is directly incurred by the city of Pittsburgh. We don't even get to share it.”
While it is unclear how much taxpayers in Pittsburgh will pay for police overtime, a Trump rally last month in Cleveland cost the city $68,000.