The University of Southern California has canceled its main graduation ceremony, the school announced Thursday.

"With the new safety measures in place this year, the time needed to process the large number of guests coming to campus will increase substantially," the school said in a statement. "As a result, we will not be able to host the main stage ceremony that traditionally brings 65,000 students, families, and friends to our campus all at the same time and during a short window from 8:30 a.m. to 10 a.m."

The individual school commencement ceremonies will continue as planned, it said.

The decision comes after USC had previously canceled this year's valedictorian speech while citing potential threats regarding the selection of the valedictorian, who expressed pro-Palestinian views on social media. It subsequently canceled all commencement speakers.

Law enforcement cleared a quad at Emory University where students had erected an encampment, the Atlanta university said.

A "couple of dozen people" were taken into custody, the university said. It did not have information on exactly how many people were taken into custody or what charges, if any, have been filed.

Emory previously said that dozens of protesters who were not part of the school community had trespassed onto the campus early Thursday morning and erected tents on the quad. Some members of the school community later joined, it said.

"Emory Police issued multiple warnings asking the crowd to disperse. When those requests were ignored, Atlanta Police and Georgia State Patrol assisted Emory Police with clearing the Quad," the university said.

Footage showed officers escorting detained protesters off campus, including in one case appearing to deploy a stun gun on an individual handcuffed on the ground.

The University of California, Los Angeles said it is "actively monitoring" a demonstration after students erected an encampment Thursday morning.

"Our top priority is always the safety and wellbeing of our entire Bruin community," Mary Osako, a UCLA spokesperson, said in a statement. "We're actively monitoring this situation to support a peaceful campus environment that respects our community's right to free expression while minimizing disruption to our teaching and learning mission."

Access to the campus' Royce Hall and Powell Library has been restricted to students who present ID, the university said.

Students for Justice in Palestine, University of California Los Angeles, one of the organizers of the encampment, called on the university to divest of funds from Israeli military operations and said in a social media post that they are "staying until our demands are met."

Brown University students began an encampment on campus Wednesday, with a student group warning other students that the university is threatening to crack down on protesters.

"Brown admin is using unprecedented repressive tactics to prevent peaceful student protest. They are doing random ID sweeps to identify people and threatening disciplinary action," the Brown Divest Coalition said in a statement on Instagram.

Students participating in the encampment "have been informed they will face conduct proceedings," Brown said in a statement to ABC News, because the encampment on the university's "greens" is a violation of policies. Brown added it has supported previous protests and activism on campus, including a hunger strike, that were "within the bounds of our policies."

"Protest is an acceptable means of expression at Brown, but it becomes unacceptable when it violates University policies that are intended to ensure the safety and security of members of the Brown community and that there is no interference in the rights of others to engage in the regular operations of the university. Early on Wednesday and periodically since, the University asked all participants in the encampment to present their Brown IDs to verify association with Brown for safety and security reasons and to appropriately address violations of policy," Brown said in a statement to ABC News.

"University administrators and the Department of Public Safety will continually monitor the situation and act as necessary. We have been troubled by reports of violence, harassment and intimidation at some encampments on other campuses, but we have not seen that kind of behavior at Brown. Any such behavior would not be tolerated," Brown said.

-ABC News' Nadine El-Bawab

More than 100 people were arrested and four police officers were injured early Thursday when Boston police moved to clear a pro-Palestinian encampment at Emerson College. It is one of several set up by students at Massachusetts colleges including Massachusetts Institute of Technology and Harvard University.

Three of the officers suffered minor injuries and a fourth officer suffered more serious injuries, according to Boston police.

None of the protesters in custody have reported injuries, according to police. The protesters will be arraigned at Boston Municipal Court.