In a message to the campus community Monday, Massachusetts Institute of Technology President Sally Kornbluth gave students until 2:30 p.m. to leave the encampment on campus.

However, protesters remained in the area until after the deadline. It's unclear if police will move in and make arrests.

"In short, this prolonged use of MIT property as a venue for protest, without permission, especially on an issue with such sharp disagreement, is no longer safely sustainable," Kornbluth said.

The encampment on MIT’s campus, on the Kresge lawn, has been ongoing for more than two weeks, according to Kornbluth.

Police moved in on an encampment at the University of California, San Diego early Monday morning, dismantling it and arresting 64 people, according to authorities.

There were 40 students among those arrested, with officials saying they "have been or will be placed under immediate interim suspension."

All classes were moved to remote learning and nonessential personnel were asked to remain home.

Several dozen protesters were detained on UCLA’s campus Monday morning, according to Los Angeles ABC station KABC.

University officials said all classes would be held remotely Monday “due to ongoing disruptions,” and police would be stationed around campus.

Harvard University students who continue to take part in the pro-Palestinian protest encampment at the school will be “referred for involuntary leave,” the university’s interim president, Alan M. Garber, said Monday.

In a letter to the student body, Garber called on protesters “to end the occupation of Harvard Yard,” arguing that the encampment “favors the voices of a few over the rights of many who have experienced disruption in how they learn and work at a critical time of the semester.”

Students placed on involuntary leave “may not be able to sit for exams, may not continue to reside in Harvard housing, and must cease to be present on campus until reinstated,” he wrote.

“As an academic institution, we do not shy away from hard and important questions,” Garber wrote. “There are many ways for our community to engage constructively in reasoned discussion of complex issues, but initiating these difficult and crucial conversations does not require, or justify, interfering with the educational environment and Harvard’s academic mission.”

-ABC News' Julia Reinstein

NYPD officers entered the campus of the City College of New York late Tuesday night.

"As requested by the university, we are currently on campus to assist the university in dispersing those trespassing," NYPD Deputy Commissioner of Operations, Kaz Daughtry, said in a post on X, sharing video of the police moving in.

In a note to the campus community, university president Vince Boudreau, said protests on campus presented "heightened challenges."

"Most importantly, this is not primarily a CCNY demonstration, and perhaps not primarily a CUNY demonstration. The significant inclusion of un-affiliated external individuals means that we don’t have established connections to them," Boudreau's letter read.

He continued: "Specifically, this demonstration has been more contentious and violent than anything we’ve seen on campus before. Today, we distributed a letter to members of the encampment detailing specific examples of threats to the safety of people within and outside the encampment, so that all of them understand the full scope of the activity. We also want all of them, and those of you reading this note, to understand that in no way does our response to this particular and extraordinary threat overwrite our more fundamental commitments to free speech, academic freedom, or the right to peacefully protest that comply with CCNY and CUNY regulations."

Boudreau said the encamped demonstrators were told to take down their encampment and follow CUNY guidelines for "future activities."

The university president also said classes would be remote on Wednesday due to the situation on campus.

-ABC News' Jolie Lash and Victoria Arancio