Counter demonstrators greatly outnumbered white nationalist Richard Spencer's supporters on Thursday at the University of Florida, their chants drowning Spencer out during his speech.
Outside, hundreds more people protested with signs and anti-Nazi chants alongside hundreds of police officers there to prevent violence.
Anti-Spencer protesters shouted, "Not in our town! Not in our state! We don't want your Nazi hate!" and "Let's go Gators" during his speech, frustrating the head of the National Policy Institute.
Three or four skirmishes occurred during the long afternoon after single Spencer supporters confronted the counter demonstrators, trying to speak and rile the crowds up. One man, wearing a white shirt with swastikas drawn on, was punched and chased out of the area. At least three others were quickly surrounded by crowds that shouted them down, chanted "Whose streets? Our streets!" and pushed them until they left the area or were chased behind police lines.
The Alachua County Sheriff said at least one person, Sean Brijmohan 28, was arrested. The office said in a tweet that he had brought a gun onto the campus after being hired by a media organization as security.
The school estimated it would spend $600,000 on security to ensure no repeat of violent clashes connected to a white nationalist gathering in Charlottesville, Virginia, that left one dead in August.
School officials cited the Charlottesville violence in rejecting an initial request from Spencer to speak at the university. They later relented on free speech grounds.
Florida's governor had declared a state of emergency for the event.