Columbia University has begun suspending student demonstrators after they defied an ultimatum to disperse.

The New York University, the epicentre of pro-Palestinian protests that have upended college campuses across the United States, made the call on Monday.

The move follows almost two weeks of protests against Israel’s war in Gaza, which have swept through higher education institutions from coast to coast, and spread into Europe. The demonstrators have demanded that the universities cease all investment in Israel or companies that are seen as supporting its war effort.

The response of the authorities has been tough, with critics of the protests referring to sporadic instances of anti-Semitism. About 100 protesters were arrested at Columbia on April 18.

In the latest crackdown, authorities at the prestigious university in New York had demanded that the protest encampment be cleared by 2pm (18:00 GMT) or students would face disciplinary action.

“These repulsive scare tactics mean nothing compared to the deaths of over 34,000 Palestinians,” said a statement, read out by a student at a news conference after the deadline passed, referring to the death toll in Gaza.

“We will not move until Columbia meets our demands or … [we] are moved by force,” said the student.

A few hours later, Columbia vice president of communications, Ben Chang, said the university had “begun suspending students as part of this next phase of our efforts to ensure safety on our campus”.

He said students had been warned they would be “placed on suspension, ineligible to complete the semester or graduate, and will be restricted from all academic, residential, and recreational spaces”.

Meanwhile, at the University of Texas in Austin, police used pepper spray as they clashed with protesters on Monday. Arrests were made as they dismantled an encampment, adding to the more than 350 people detained nationwide over the weekend.

“No encampments will be allowed,” Texas Governor Greg Abbott said on social media. “Instead, arrests are being made.”

Protests against the Gaza war, with its high Palestinian civilian death toll, 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.

Footage of police in riot gear summoned at various colleges to break up rallies has been viewed around the world, recalling the protest movement that erupted during the Vietnam War.

Columbia University president, Minouche Shafik, in a statement on Monday announcing talks had broken down, said, “Many of our Jewish students, and other students as well, have found the atmosphere intolerable in recent weeks.

“Many have left campus, and that is a tragedy,” she continued. “Anti-Semitic language and actions are unacceptable and calls for violence are simply abhorrent.”

Protest organisers deny accusations of anti-Semitism, arguing their actions are aimed at Israel’s government and its prosecution of the conflict in Gaza.

They also insist there have been incidents engineered by non-student agitators.