Protesters at the University of Pennsylvania loudly interrupted the director of the Central Intelligence Agency, John O. Brennan, less than 15 minutes into a moderated discussion last Friday, and subsequent interruptions ended the event early, reports the campus’s student newspaper, The Daily Pennsylvanian.

According to the newspaper, the event was held by the Fels Institute of Government and other organizers, including the university’s Center for International Politics. Attendees were required to register in advance and present identification at the door.

A YouTube video shows protesters shouting “drones kill kids” and “U.S. out of the Middle East” before being escorted out of the event, which was held at the university’s Museum of Archaeology and Anthropology. The video also shows a couple of protesters holding a sign that says, “Drone Strikes Breed Terrorism.”

The situation is similar to what happened at Brown University in the fall of 2013, when protesters shut down a lecture by a former commissioner of the New York City Police Department, Raymond W. Kelly, and other such controversies on campuses nationwide. Events like those have left college administrators struggling with if, and when, they ought to cancel controversial speakers.