UC Berkeley hosted a panel called Front Row consisting by successful people coming from the Bay Area like Primus’ Les Claypool, CEO of Salesforce.com Marc Benioff, and Metallica’s James Hetfield and Lars Ulrich among others speaking about how they achieved their goals coming from the region and succeeded in their fields. Unfortunately, the event was disrupted during Ulrich’s speech by a group of protesters who resorted to violence to stop the panel.

During the first night of the event, Ulrich gave the opportunity to students to speak and get involved in the panel and later proceeded to interview Benioff but during the conversation, a small student group that calls itself the Student Labor Committee, or SLC, decided to use physical violence in protest, attacking Benioff before getting tackled by law enforcement.

It is not clear exactly what caused incident aside from their claims that it was directly targeted towards Benioff and that they were acting within their own freedom of speech but things really turned ugly. You can watch footage of the incident below: