LOS ANGELES (AP) Counter-protesters forcefully attacked a pro-Palestinian encampment at UCLA early Wednesday, the universitys chancellor said, and activists clashed with police officers who destroyed their tents at the University of Wisconsin in Madison, part of a series of escalating violence on some college campuses over the war in Gaza.

UCLA administrators and campus police delayed intervening and calling for law enforcement backup in the brawl on the Los Angeles campus, prompting widespread condemnation from Muslim students to the citys mayor to California Gov. Gavin Newsom.

The counter-protesters, some of whom carried Israeli flags, threw traffic cones and chairs, released pepper spray, and pulled down the barricade surrounding the encampment. University officials said 15 people were injured in the confrontation, including one person who was hospitalized.

The chaotic scenes unfolded Wednesday after police burst into a building occupied by anti-war protesters at Columbia University on Tuesday night, breaking up a demonstration that had paralyzed the school.

Chancellor Gene Block at UCLA said in a statement that a group of instigators came on campus Tuesday night to forcefully attack the pro-Palestinian encampment.