Four hours into the protest against a conservative pundit's appearance at the University of California (UC) Berkeley in the United States, violence escalated when police began pushing protesters down Telegraph Avenue.

Protesters and supporters of Ben Shapiro began gathering at 4pm (23:00 GMT) on Bancroft Way on Thursday, many having travelled hours by car or plane.

While many of them seemed excited to see Shapiro or to speak against him, an equal number simply wanted to experience the type of action they would read about in the news.

"I'm excited to see Antifa in action," Justin Jackson, a 19-year-old student at Chico State University who had driven three hours to the event, told Al Jazeera.

"Antifa and Shapiro in the same day is exciting," said his friend Liam Thomson, referring to a broad group of autonomous anti-fascist activists in the US.

But by the end of the night, Antifa had not appeared.

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Well over a hundred police from all over the state spread over the two blocks. In the hours leading up to Shapiro's speech, they arrested two protesters.

Twenty-year-old Hannah Benjamin spat on a police officer and was arrested on charges of felonious assault.

Sarah Roark, 44, was also arrested for holding a sign that police considered a banned weapon because it was too large.

Authorities said several further arrests were made later.

Inside Zellerbach Hall, Shapiro's speech fell in line thematically with the content of his radio show, to the delight of his fans.

"Let me suggest to you that if you need counselling because of this speech," he began.

"You're a pussy!" finished a fan who was wearing a Border Patrol cap. The audience cheered.

Shapiro also made points about the virtue of following a traditional lifestyle and of self-reliance.

The US is the "greatest place that ever existed" he said, adding that everyone who was a "failure" had only themselves to blame.

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Shapiro is the third controversial right-wing speaker the Berkeley Campus Republicans and Young America's Foundation, two conservative youth organisations, have invited to speak on campus this year.

The previous two, former Breitbart editor Milo Yiannopoulos and conservative commentator Ann Coulter, cancelled their engagements due to safety concerns.

Shapiro is known for his divisive political views. He is against abortion rights and has spoken out against US President Donald Trump and Steve Bannon, Trump's former senior counsellor.

Unlike Yiannopoulos, he does not identify as a member of the recently emerged alt-right, which he has called "one of two twin cancers eating America".

The alt-right, in turn, has targeted him for his views and Jewish background.

A 2016 report by the Anti-Defamation League found that Shapiro was the number one target of anti-Semitic violence on Twitter.

The anti-fascist organisation, RefuseFascism.org, organised the protest against Shapiro, which they called "Berkeley Speak Out: Against white supremacy, misogyny and fascism."

The night before the event, RefuseFascism.org advisory board member Sunsara Taylor said Shapiro's often-contradictory statements "disarm" people and "legitimise" violent speech.

"We need people to come and sound the alarm on this," said Taylor.

Berkeley community members agreed. One group of over two dozen students hid in the building hours before the police showed up. At about 6:45pm (21:45 GMT), they gathered on the balcony above the entrance to protest the event.

Two hours later, police let the students leave in groups of two, to applause and drumbeats.

After Shapiro's speech ended, attendees were herded out the opposite side of the building for safety reasons, according to police. But many returned to the site of the protest. One woman was injured, hitting her head on the pavement.

In a campus-wide email, UC Berkeley Chancellor Carol Christ defended Shapiro's right to come to campus, citing the school's ongoing commitment to free speech.

Dan Mogulof, assistant vice chancellor in the office of public affairs and the campus' primary spokesperson, estimated that administrators had spent $600,000 on the event.

Shapiro's speech is one of many scheduled in the next few weeks, including Milo Yiannopoulos' "Free Speech Week." Yiannopoulos will be joined by Ann Coulter, Steve Bannon, and Mike Cernovich for the event.

Andrew Beale and Josh Slowiczek contributed to the report