Pro-Palestinian student protesters and their pro-Israeli counterparts clashed at the campus of the University of California, Los Angeles (UCLA) Wednesday as demonstrators who barricaded themselves inside a building of Columbia University in New York were arrested.

UCLA protesters and counter-protesters were seen clashing with sticks, and tearing down metal barricades, TV images showed.

The university Chancellor called the LA police department for support on campus and it responded immediately, according to Zach Seidl, a spokesperson for the city mayor, in a post on social media platform X.

Others were seen launching fireworks or hurling objects at each other in the dark — lit up with laser pointers and bright flashlights.

UCLA Chancellor Gene D. Block warned ahead of clashes that protesters including “both members of the UCLA community and others unaffiliated with our campus” had set up a camp last week.

Some demonstrators resorted to violence, he claimed, putting Jewish students in a state of anxiety and fear, Block added.

In Columbia University, dozens of helmeted police flooded the campus on Tuesday to evict pro-Palestinian student protesters occupying a building and to detain demonstrators.

‘That is not an example of peaceful protest.’

Police climbed into Hamilton Hall via a second floor window they reached from a laddered truck, before leading handcuffed students out of the building into police vans.

The hall had been barricaded from the inside at dawn by demonstrators who vowed they would fight any eviction, as they protested the soaring death toll from Israel’s war with Hamas in the Gaza Strip.

The action came as university administrators around the US have struggled for weeks to contain pro-Palestinian demonstrations on dozens of campuses.

In a letter addressed to the New York Police department, Columbia University president Minouche Shafik said that the occupation of the school building was being led by “individuals who are not affiliated with the University” and asked “NYPD’s help to clear all individuals from Hamilton Hall and all campus encampments.”

She also asked the police to remain on campus through at least 17 May, “to ensure encampments are not reestablished.”

President Joe Biden’s White House had sharply criticized the seizure of Hamilton Hall, with a spokesperson saying it was “absolutely the wrong approach.”

“That is not an example of peaceful protest,” the spokesperson added.

The protests, with Columbia at their epicenter, have posed a challenge to university administrators trying to balance free speech rights with complaints that the rallies have veered into anti-Semitism and hate.

The unrest has swept through US higher education institutions like wildfire, with many student protesters erecting tent encampments on campuses from coast to coast.

At Columbia, demonstrators have vowed to remain until their demands are met, including that the school divest all financial holdings linked to Israel.

The university has rejected the demand. Columbia has warned that students occupying the building face expulsion.