STORY: UCLA's campus was packed with a heavy police presence on Wednesday, after violent clashes erupted overnight between supporters of Israel and pro-Palestinian demonstrators.

Footage from the early hours on Wednesday showed a firework being thrown into the pro-Palestinian protest camp.

More witness footage from UCLA, which was verified by Reuters, showed people wielding sticks or poles to hammer on wooden boards being used as makeshift barricades to protect the pro-Palestinian protesters before police were deployed to the campus.

Some screamed pro-Jewish statements as pro-Palestinian protesters tried to fight them off including Kaia Shah, a researcher at UCLA.

"They were coming up here and just violently attacking us, it was honestly something that I, I'm kind of annoyed at myself for not seeing it coming, but I just didn't think they would ever get to this, escalate to this level, where our protest is met by counter-protesters who are violently hurting us, inflicting pain on us, when we are not doing anything to them."

Demonstrators on both sides sprayed each other with unknown substances and fights broke out.

Calm was later restored after police arrived on the scene.

The violence followed an announcement on Tuesday by UCLA administrators that the encampment was unlawful and violated university policy.

The school's chancellor said it included people unaffiliated with the campus, though he provided no evidence of the presence of outsiders.

The Oct. 7 attack on southern Israel by Hamas militants from the Gaza Strip and the ensuing Israeli offensive on the Palestinian enclave have unleashed the biggest outpouring of U.S. student activism since the anti-racism protests of 2020.

In New York Wednesday, sanitation workers swept up shattered glass just outside Columbia University's Hamilton Hall, which had been occupied by pro-Palestinian demonstrators.

New York City Mayor Eric Adams said about 300 people had been arrested in the action Tuesday night, and he blamed the protests on outside agitators, without offering concrete evidence.

Police were also called in to clear encampments and make arrests overnight at Tulane University in New Orleans, the University of Arizona, and The City College of New York in Harlem.