Ann Coulter was a presence even in her absence in Berkeley Thursday.

The conservative firebrand backed away from making a controversial visit to the home of the University of California. But the furor over her cancelled appearance still brought hundreds of protesters and a massive police presence to the campus and a nearby city park.

University spokesman Dan Mogulof said police had obtained "a lot of information about threats [from] individuals and groups who intend to either come and protest all that's happening or support all that's happening."

Berkeley police said Thursday night that "demonstration-related activity" had ended without any major confrontations. Police said they confiscated "numerous" weapons throughout a long day of gatherings at several on and near the U.C. Berkeley campus.

But no one was hurt and just five people were arrested — two for resisting arrest, one for carrying a knife, one for attempting to incite a riot and one for possession of a controlled substance.

Demonstrators hold signs and flags on April 27, 2017, in Berkeley, Calif. Marcio Jose Sanchez / AP

An on-campus demonstration — with speakers both for and against Coulter — broke up in the early afternoon. But demonstrators continued to mass west of the campus in Martin Luther King Jr. Civic Center Park. Some were vocal supporters of President Trump, saying they came to back Coulter's First Amendment rights. Others described themselves as progressives, who came to oppose what they said was the author's divisive rhetoric.

By late afternoon Thursday, all that had broken out between the pro- and anti-Coulter forces were a few shouting matches and many more spirited arguments. But tensions remained high, in part because some protesters came dressed in helmets, masks and other conflict-ready gear and in part because of Berkeley's recent history. Two disagreements over conservative speakers slated to appear on campus in recent weeks have erupted into violence.

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Appearing on Fox News's "Tucker Carlson Tonight" Thursday evening, Coulter continued to chide Berkeley authorities, mocking a police administrator who said Coulter couldn't have been adequately protected if she showed up this week.

"Well, I don’t know, call a cop," Coulter said to Carlson. "What’s your job? It's like you're on a plane that is about to take off and the pilot says 'How am I supposed to get this thing across the country?' That’s your job!”

Thursday's standoff grew out of a plan by two campus organizations to have Coulter speak on campus. Campus officials denied the request, saying that they had not been given enough time to find an appropriate time and place for the appearance by the columnist and television personality. They said they needed a venue that could be "secured," in order to protect students, guests and Coulter herself.

But Coulter and her would-be hosts, including the Berkeley College Republicans, said the university's fears were overblown and that Thursday's mass police presence proved that they could have been ready for any eventuality.

Coulter insisted that her appearance had been cancelled not merely postponed and claimed an irony that the action had been taken on a campus where the Free Speech Movement was born in the 1960s. "It's sickening when a radical thuggish institution like Berkeley can so easily snuff out the cherished American right to free speech," she said in one of a string of provocative tweets.

Related: How Berkeley Became a New Battleground for Free Speech

But even as she officially pulled out of the Berkeley event Wednesday, Coulter claimed more attention by suggesting in an email to the Associated Press she might show up on campus anyway.

“I’m not speaking. But I’m going to be near there, so I might swing by to say hello to my supporters who have flown in from all around the country,” Coulter wrote. “I thought I might stroll around the graveyard of the First Amendment.”

Slams on the university administration continued Thursday, with the Berkeley College Republicans also claiming that Berkeley's attempt to delay the event until next week amounted to shunning Coulter for her political views. Naweed Tahmas of the Berkeley College Republicans said that police were "doing a fantastic job right now" in showing they could keep the peace.

He called the action in redirecting Coulter to another date "a poor precedent for a university, an academic institution where freedom of speech should be championed and there should be an open flow of ideas and an open dialogue."

But university leaders said the proof that they were not blocking Coulter because of her conservative views was made clear by their invitation for her to come to the campus as early as May 2.

Mogulof, assistant vice chancellor for public affairs at Berkeley, said the campus was locked in a "tension" — between two imperatives — enabling free speech and protecting students and others.

"Our commitment to the First Amendment, to free speech, is non negotiable," he said. "But we can't turn a blind eye to the realities beyond the walls of this campus. And that reality includes individuals and organizations who are willing to do violence and willing to use the university as a battleground.”

Had she appeared in Berkeley Thursday, Coulter told the Fox channel's Carlson, she would have spoken about the needed to secure America's borders. She chided President Trump and Republicans for not pushing ahead this week with their earlier demand for initial funding for a wall along the U.S.-Mexico border.

Coulter had written in her column, posted earlier in the day, that Trump's inability to push ahead with the wall amounted to abandonment of one of his most important campaign promises.

"He's the commander in chief! He said he'd build a wall," Coulter wrote. "If he can't do that, Trump is finished, the Republican Party is finished, and the country is finished."