Tensions at the University of California, Irvine campus escalated on Wednesday as a group of several hundred pro-Palestinian Arab protesters entered a lecture hall and surrounded the building, ABC News reported, citing school officials.
The Irvine Police Department and the Orange County Sheriff's Department were called to the scene after the university called for mutual aid from local law enforcement agencies, UC Irvine said in an emergency update.
Authorities have begun making arrests, though the number is unknown at this time.
The protesters had entered the Physical Sciences Lecture Hall on the UC Irvine campus at approximately 2:30 p.m. local time, according to the university.
Classes for the remainder of the day were canceled and school officials urged anyone in the immediate area to evacuate until further notice.
Pro-Palestinian Arab protesters have been present on the UC Irvine campus since establishing an encampment on April 29.
The UC Irvine encampment is one of many that have been set up at campuses across the US in recent weeks.
Last Thursday, LAPD and California Highway Patrol cleared an anti-Israel protest encampment on the UCLA campus, arresting 132 people.
Later, the Los Angeles Police Department removed a pro-Palestinian Arab encampment at the University of Southern California, pushing several dozen people out of the campus gates.
In another incident, police in riot gear cleared an anti-Israel encampment at the University of Chicago.