Twenty-three people were arrested Saturday at an encampment at Indiana University, the university said.

A group erected tents and canopies on the Bloomington campus' Dunn Meadow Friday night "with the stated intention to occupy the university space indefinitely," in violation of school policy, the university said in a statement.

University and state police gave the group "multiple warnings" midday Saturday to remove the structures before detaining them for charges ranging from criminal trespass to resisting law enforcement, the university said. It is unclear what their affiliation with the university is, the school said.

"The Indiana University Police Department continues to support peaceful protests on campus that follow university policy," the university said in a statement.

The IU Divestment Coalition, a Pro-Palestinian campus group that organized the protest, said many of those arrested were students.

"They are trying to intimidate us, they are trying to break our spirit and our organizing but we will continue to stand for Gaza," the group said on social media.

Ohio State University police have arrested 36 people -- 16 of whom were students -- and charged them with criminal trespassing for encampments that remained overnight.

"Well established university rules prohibit camping and overnight events. On Thursday, April 25, demonstrators, a number of whom were not students, faculty or staff at Ohio State, exercised their First Amendment rights for several hours and were then instructed to disperse," OSU said in a statement.

"Individuals who refused to leave after multiple warnings were arrested and charged with criminal trespass. Arrests are not an action that we take lightly, and we appreciate the support of all of our law enforcement partners to disperse the encampment for the safety of our university community. We have always, and always will, take the action that is in the best interest of our community," OSU said.

Arizona State University announced that campus police have arrested 69 people for trespassing after protesters refused to leave a pro-Palestinian encampment that the university says was "unauthorized."

"Encampments are prohibited on Arizona State University property. Lawful demonstrations can take place except overnight between 11 p.m. and 5 a.m.," ASU said in a statement.

"A group of people – most of whom were not ASU students, faculty or staff – created an encampment and demonstration that continued until 11 p.m. when the group was instructed multiple times to disperse. Individuals who refused to leave after multiple warnings were arrested and charged with criminal trespass," ASU said.

Northeastern University has removed an encampment of pro-Palestinian protesters, with police detaining about 100 people. The university says students who produced valid Northeastern ID were released and will face disciplinary proceedings within the university.

"Earlier this morning the Northeastern University Police Department -- in cooperation with local law enforcement partners - began clearing an unauthorized encampment on the university's Boston campus. What began as a student demonstration two days ago was infiltrated by professional organizers with no affiliation to Northeastern. Last night, the use of virulent antisemitic slurs including "Kill the Jews," crossed the line. We cannot tolerate this kind of hate on our campus," the university said in a statement.

The university added, "As part of clearing the site, approximately 100 individuals were detained by police. Students who produced valid Northeastern ID were released. They will face disciplinary proceedings within the university, not legal action. Those who refused to disclose their affiliation were arrested."

Massachusetts State Police said they responded to Northeastern's request for assistance removing protesters.

"Officers directed protesters to disperse and MSP members assisted in removing protesters who refused to leave. Approximately 102 protesters who refused to comply with orders to disperse were arrested and will be charged by NUPD with trespassing and disorderly conduct. They are being transported to the Suffolk County House of Correction to be booked and processed," MSP said in a statement.

New York University students set up a new pro-Palestinian encampment Friday, after over 130 students and faculty were arrested at an encampment earlier this week.

The protesters are calling on the university to divest and cut ties with Israel and companies profit from its onslaught on Gaza — including shutting down the NYU Tel Aviv campus and a boycott of Tel Aviv University. They are also calling for full amnesty for pro-Palestinian activism and for IOF-trained cops to leave campus.

"Despite the violent repression students have face, we will not back down. We have no reason to fear when Palestinians demonstrate their courage and resiliency in the face of far greater danger. Our fear has turned into resolve," the NYU Palestine Solidarity Coalition said in a statement Saturday.

Protesters say they were removed and arrests were made at a "100% peaceful" protest earlier this week, refuting the university's allegation that there was "antagonizing behavior" and a security breach caused it to invite New York police onto campus and make arrests, a representative for the NYU PSC told ABC News.

Protesters say they calmly entered the encampment after the university did not follow through on providing a timeline of when they would allow more students into the plaza, according to the student who was at the protest outside the encampment, but was not arrested.

Police started making arrests Monday after Muslim protesters began Maghreb prayer -- a daily Muslim prayer made during the sunset hour -- according to the student.

"Our peaceful protest was met with complete and utter violence green lighted by our university president and her administration," the student, who asked that ABC News conceal their identity for safety, said.

The university pushed back against the protester's account, saying "there is no right to create encampments of tents on the University's property."

"Despite repeatedly being told no additional protesters would be permitted on the plaza - early on Monday afternoon protesters on West 4th Street breached the barricades we had set up, nearly doubling the number of people on the plaza, with hundreds of additional demonstrators in the street," NYU said in a statement to ABC News.

"Those on the plaza urged them onwards and that Campus Safety Officers were shoved and forced out of the way by people attempting to gain entry to the plaza," NYU said.

-ABC News' Nadine El-Bawab