DePaul University cancelled an event for conservative political commentator Ben Shapiro to address students and said he will not be allowed to step foot on campus due to security concerns.

DePaul’s Young Americans for Freedom, or YAF, chapter booked Shapiro to speak on campus at the private university in Chicago, but the school revoked the invitation.

Bob Janis, DePaul’s vice president of operations, sent an email to the YAF chapter’s executive board saying, "Given the experiences and security concerns that some other schools have had with Ben Shapiro speaking on their campuses, DePaul cannot agree to allow him to speak on our campus at this time."

This is not the first time Shapiro has been blocked from speaking at a university. The conservative pundit was banned from speaking at California State University last February, resulting in protests from students when Shapiro decided to show up anyway.

YAF defending Shapiro in a statement responding to Janis’ email.

For the past six months, we have worked with Ben on a high-profile tour of college campuses and witnessed with our own eyes the vicious and threatening behavior of tyrannical leftists who have been programmed by progressive administrators to silence all speech they disagree with. If DePaul cannot trust its delicate liberal snowflake students and administrators to allow Ben to speak his mind safely and freely, it has utterly failed in its mission to "[foster] a community that welcomes open discourse." Make no mistake, any security concerns we face on campuses are 100 percent incited by the censorious, intolerant Left. DePaul should publicly thank its Young Americans for Freedom chapter for boldly doing the school’s job of providing "exposure to differing points of view" for it and allow Ben to speak, not begrudgingly, but happily. It’s incumbent upon the intolerant Left, not hardworking YAF students, to allow conservatives to express their viewpoints without fearing for their safety. Thankfully, Ben, and YAF activists across the country, believe deeply enough in free speech to fight for their values, even as the Left attempts to intimidate them from even speaking. If DePaul does not reverse its decision to ban Ben, it must immediately remove any claim to support free speech and expression from its website and marketing materials or become a fraudulent laughingstock.

Shaprio responded to DePaul cancelling his event on Twitter.

So, I've been banned from DePaul. Because they're cowards. https://t.co/hBg1yzLz46 — Ben Shapiro (@benshapiro) August 1, 2016

He tweeted out the dean’s email encouraging students to stand up against the ban.

If you'd like to let the DePaul's dean know that political bans are wrong, feel free to email (politely, please!): deanofstudents@depaul.edu — Ben Shapiro (@benshapiro) August 1, 2016

The Young Americans for Freedom’s DePaul chapter has asked the university to reverse their decision.