Milo Yiannopoulos event at UC Berkeley canceled amid protests bordering on riots, with fires, small concussion bombs and rocks thrown. (Christopher Keiser/Newsweek)

Conservative journalist Milo Yiannopoulos’ tour of college campuses met opposition once again Wednesday night when hundreds of protesters launched a violent demonstration at the University of California, Berkley, forcing the police to cancel his planned appearance.

“This is not a proud night for this campus, the home of the free speech movement,” Berkeley spokesman Dan Mogulof told the Los Angeles Times.

The event was called off about two hours before Yiannopoulos was scheduled to speak as protesters threw metal barricades, smashed windows and set fires at the university's student union. President Donald Trump tweeted about the protests Thursday morning, threatening to cancel federal funding for UC Berkeley:

Yiannopoulos, an editor for the right-leaning Breitbart News, has sparked controversy in the past with remarks about feminism, the “liberal left” and Islam. He's known for his support of Trump, for whom he advocated for during the presidential election as the politician "best placed to end the cancer of political correctness in this country,” as he said at a Trump rally in Cleveland in July.

Here are five other things to know about Yiannopoulous:

Yiannopoulos is a Greek-born British journalist and editor for Breitbart News. His articles boast controversial headlines on the far-right website, including titles like “The Solution To Online ‘Harassment’ Is Simple: Women Should Log Off” and “The Left Chose Islam Over Gays. Now 100 People Are Dead Or Maimed In Orlando.”

He openly identifies as gay but has said he believes homosexual men should follow a more "traditional" family role similar to the 1950s where "gay men would “live a lie,” get married and have kids. “Forcing gays back into the closet also solves the problem of what happens to children when they have two dads or two moms. Children raised in gay households are more likely to suffer mental problems, more likely to end up gay themselves and, if raised by lesbians, almost certain to witness domestic abuse,” Yiannopoulos wrote.

His tour has been previously met with protests and objections from college students on several campuses. The University of California, Davis’s College Republicans organization scheduled an event for Yiannopoulos and pharmaceutical executive Martin Shkreli to appear at their university in January, but it was canceled after protesters blocked the venue and reportedly made the event unsafe.

Yiannopoulos has announced a book deal with Simon & Schuster in December 2016. The book, titled “Dangerous,” sparked a backlash: Author Roxane Gay eventually decided to pull a book she planned to release with the publisher, citing Yiannopoulos’s “inelegant hate and provocation” as the reason why she did not want to share the same publishing platform.

He was banned on Twitter in July 2016. Yiannopoulos reportedly posted offensive tweets about Ghostbusters star Leslie Jones, causing the social media site to permanently suspend him. “People should be able to express diverse opinions and beliefs on Twitter. But no one deserves to be subjected to targeted abuse online, and our rules prohibit inciting or engaging in the targeted abuse or harassment of others,” a Twitter spokesperson told BuzzFeed News at the time.