Clashes at UCLA as police retake Columbia building

Clashes broke out on at pro-Palestinian demonstrations on the campus of the University of California, Los Angeles, as dozens of universities around the United States struggled to contain similar protests.

Protesters and counter-protesters were seen clashing with sticks, and tearing down metal barricades.

Others were seen launching fireworks or hurling objects at each other in the dark - lit up with laser pointers and bright flashlights. Tear smoke was also fired at rival protesters.

The Los Angeles police department had said it was responding "due to multiple acts of violence within the large encampment" after the university asked for help to quell the clashes.

UCLA chancellor Gene 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.

"Many of the demonstrators ... have been peaceful in their activism," Block posted on the university website.

"But the tactics of others have frankly been shocking and shameful. We have seen instances of violence."

The unrest at UCLA comes after police cleared Columbia University's campus in New York City and evicted a building occupied by pro-Palestinian student protesters.

Demonstrators vowed they would fight any eviction, as they protested the soaring death toll from Israel's war with Hamas in the Gaza Strip.

Columbia University president Minouche Shafik had said in a letter to police that the occupation of the school building was being led by "individuals who are not affiliated with the university."

She also asked police to remain on campus through at least May 17 "to ensure encampments are not reestablished."

The weeks of demonstrations have led to several hundred arrests.

President Joe Biden's White House had sharply criticized the seizure of Columbia's Hamilton Hall, with a spokesman saying it was "absolutely the wrong approach."

At University of Arizona, police said they were "deploying chemical irritant munitions" to disperse "an unlawful assembly."

At University of North Carolina, police moved to clear one encampment, detaining some protesters in a tense showdown.

A week-long occupation was brought to an end at northern California's Cal Poly Humboldt while Portland State University's campus, in Oregon, was closed "due to an ongoing incident."

And Brown University reached an agreement in which student protesters will remove their encampment in exchange for the institution holding a vote on divesting from Israel - a major concession from an elite university.