Columbia University has been thrust into turmoil in recent weeks, reeling from a congressional hearing on antisemitism with President Minouche Shafik, NYPD’s arrest of more than 100 who protest in support of Palestinians on the university’s lawn, and the occupation of the campus' Hamilton Hall.
Here’s a timeline of the events as they continue to unfold:
On the morning of April 17, student protesters opposed to Israel's war in Gaza have camped out throughout the Columbia University campus.
Columbia University Apartheid Divest, which states that it’s a coalition of more than 100 student groups, says it is calling for the university to financially divest from companies and institutions that “profit from Israeli apartheid, genocide and occupation in Palestine,” according to an online statement.
However, Columbia's investments are not public information and remain largely unknown.
In March, the Columbia College Student Council approved a student referendum on the issue, according to the Columbia Daily Spectator.
“As a diverse group united by love and justice, we demand our voices be heard against the mass slaughter of Palestinians in Gaza,” the group stated.
Tensions have been high on college campuses nationwide since the start of the Israel-Hamas war on Oct. 7, when Hamas terrorists invaded Israel. The Israeli military then began its bombardment of the Gaza Strip.
In the Gaza Strip, at least 34,000 people have been killed and more than 77,000 others have been wounded by Israeli forces since Oct. 7, according to the Hamas-run Gaza Ministry of Health.
In Israel, at least 1,700 people have been killed and 8,700 others injured by Hamas and other Palestinian militants since Oct. 7, according to the Israeli Ministry of Foreign Affairs.
Multiple United Nations organizations have warned that Gaza is also experiencing "catastrophic" levels of hunger amid an ongoing humanitarian crisis.
Protesters camping on the university lawn say they believe the war in Gaza amounts to “genocide” of Palestinians.
“I’m here continuing the Jewish tradition of standing against oppression and injustice, especially as we approach Passover, a holiday that celebrates our own liberation and commits us to fighting for everyone else’s,” the Jewish Voices for Peace at Columbia said in an online statement.
On the same day as the protests, Columbia President Shafik testified before the House Committee on Education and the Workforce, which has been investigating antisemitism on college campuses. The hearing comes after two of Shafik's counterparts at other elite colleges resigned amid a backlash over their responses at a previous hearing of the same panel.
In her opening statement, Shafik, who was appointed president of the Ivy League school in July 2023, told the committee that Columbia "strives to be a community free of discrimination and hate in all forms and we condemn the antisemitism that is so pervasive today."
She said a "major challenge" has been reconciling free speech with the rights of Jewish students to go to school in an environment free of discrimination and harassment.
"Regrettably, the events of Oct. 7 brought to the fore an undercurrent of antisemitism that is a major challenge and, like many other universities, Columbia has seen a rise in antisemitic incidents," Shafik said.
Shafik said she has taken actions since Oct. 7, including enhancing Columbia's reporting channels, hiring staff to investigate complaints and forming an antisemitism task force.
MORE: The Israel-Hamas war has college campuses on edge. How some are tackling the issue.Some other groups on Columbia’s campus, including Students Supporting Israel, say their needs for safety are not being met on campus.
The group described instances they say some Jewish, Israeli and Zionist students have faced, including intimidation and verbal attacks, saying the situation has become “untenable.”
“Students’ rights to peacefully attend their university courses without fear of being accosted or assaulted on their way to class were denied,” an online statement read.
An Arab-Israeli activist, Yoseph Haddad, was set to speak at the student group’s event on April 18 when he was allegedly punched by a protester outside the campus. The event was canceled, the group said.
“It’s time we end this narrative and aim for a future where both Israelis and our Palestinian neighbors can accept each others’ fundamental right to live freely and without terrorism or war,” the group stated.
Student protesters have released a statement saying that “inflammatory individuals who do not represent us” have distracted from the group’s intentions.
“At universities across the nation, our movement is united in valuing every human life,” the statement from Columbia University Apartheid Divest continued.
The statement from Columbia University Apartheid Divest added that students have been misidentified, doxxed, arrested, locked out of campus housing and more, amid the protests.
“We have knowingly put ourselves in danger because we can no longer be complicit in Columbia funneling our tuition dollars and grant funding into companies that profit from death.”
Several university and local leaders have spoken out against instances of antisemitism amid the unrest.
"I have instructed the NYPD to investigate any violation of law that is reported," New York City Mayor Eric Adams said. "Rest assured, the NYPD will not hesitate to arrest anyone who is found to be breaking the law."
On April 18, one day after Shafik’s testimony, more than 100 protesters at Columbia University were arrested and an on-campus tent encampment was removed after the school's president gave the New York Police Department the green light to clear the protesters, officials said.
"Students have the right to free speech but do not have the right to violate university policies and disrupt learning on campus," Adams told reporters during a press briefing that evening.
Around 1:30 p.m. ET, police moved in and arrested dozens of pro-Palestinian protesters, placing their hands in zip ties and escorting them to buses. Other protesters chanted "Shame!" and "Let them go."
Some 108 people were arrested for trespass without incident, officials said. Among those, two were also arrested for obstruction of governmental administration, officials said.
Isra Hirsi, the daughter of Rep. Ilhan Omar, D-Minn., was among those arrested for trespass and will be getting a summons, officials said. Hirsi said she was among several students suspended from Columbia's Barnard College for participating in pro-Palestinian protests.
The terms of her suspension are unclear.
Rep. Omar said she was "enormously proud of my daughter," in a post on X.
The tent encampment and protests have since resumed on campus in an ongoing, dayslong effort.
ABC News has reached out to Columbia University for comment.
On April 23, Barnard President Laura Rosenbury sent an email to the Barnard community, stating that the "vast majority" of students currently on interim suspension have not previously broken any college rules.
If these students choose to agree to follow Barnard's rules during a probationary period, Barnard's administration said it would lift their suspensions, allow them to regain access to Barnard buildings, and neither the interim suspension nor the probationary period would appear on their transcript or student disciplinary records, Rosenbury said.
Columbia University announced Monday that all classes on Monday, April 22, would be held remotely and only essential personnel should report to work in person. She said campus tensions have been "exploited and amplified" by people unaffiliated with the university "who have come to campus to pursue their own agendas."
"The decibel of our disagreements has only increased in recent days," said Shafik. She said a group of administrators and faculty members will come together to come to a "resolution" on campus issues and also speak with student protesters. "We need a reset."
A university public safety announcement on April 21 also outlined new resources to address "considerable disruption and distress" caused by ongoing gatherings at the campus, located in Manhattan's Morningside Heights neighborhood.
The measures include increasing security patrol with 111 additional personnel -- including more personnel for campus escort services and campus access point security -- as well as improved ID checks at entry points and increased security at The Kraft Center, which houses aspects of Jewish life on campus, during the Passover holiday which began on April 22.
NYPD told ABC News on April 22 that there are no credible threats to any particular group or individual as a result of the protests at Columbia University.
The NYPD is working with the university to provide "safe corridors" for students -- locations where officers will be stationed off-campus.
The department says it has not received any reports of physical harm toward any students.
MORE: The Israel-Hamas war is a hot-button issue. How K-12 schools are addressing it.New York Gov. Kathy Hochul met with Shafik and NYPD officials on April 22 to discuss public safety initiatives as student protests and unrest continue to play out on campus.
"Students are scared, they're afraid to walk on campus, they don't deserve that," Hochul said in a video message posted to social media.
"I'm calling on everyone. People need to find their humanity, have the conversations, talk to each other, understand the different points of view. Because that's what college students should be doing," Hochul added.
On April 24, House Speaker Mike Johnson spoke with some Jewish students on campus about their concerns, and called on the Shafik to resign unless she can improve what he called her failure to handle the anti-Israel protests on campus.
"If this is not contained quickly, and if these threats and intimidation are not stopped -- there is an appropriate time for the National Guard. We have to bring order to these campuses. We cannot allow this to happen around the country. We are better than this. We are better than this. And I will ask [President Biden] to do that, and I will tell him the very same thing," Johnson said.
On April 22, more than 150 untenured faculty members submitted an open letter in support of student protesters and against the NYPD's engagement with campus protests in the Columbia Daily Spectator, the student newspaper on campus.
"In the face of these events, we stand with you," the letter read. "You should be able to express your views and engage in peaceful protest on campus, not least in public spaces. You should certainly not be worried about being sanctioned for your political views. You should not be made fearful because police line the gates, ready to flood onto our campus at the invitation of the administration."
On April 27, more than 100 faculty members of the Barnard chapter of the American Association for University Professors unanimously issued a “no confidence” vote in Barnard President Laura Rosenbury, who runs Columbia's Barnard College, according to an open letter.
They cited a "lack of care for students," "repeated violations of academic freedom and free expression," "undermining the longstanding and cherished culture of Barnard College," and more.
Across the country, dozens of student on-campus encampments against the Israel-Hamas war have continued to pop up at colleges and universities, including: New York University, Yale University, University of Michigan, Massachusetts Institute of Technology, Tufts University, Emerson College, University of Texas-Austin and The New School.
The Hostages Families Forum, a pro-Israel group, held a mass rally on the morning of April 26 in front of Columbia University, aiming to bring the hostages back into the public discourse.
“My dream was to study at Columbia, to engage in discussions and debates on complex issues. It’s possible to debate the war and its costs," said Dana Cwaigrach, a leader of the Hostages Families Forum and a student at Columbia, in a statement. "It’s not possible to ignore and deny what happened to us on October 7th and the fact that there are still 133 hostages in Gaza.”
Leat Unger, a Columbia alumna and cousin of hostage Omer Sham Tov, added: “As a Columbia alumna, I am deeply pained by the widespread disregard for the hostages. Omer, who is the age of the students here, was kidnapped from a party. It could have been any one of you," according to a statement from the group.
On April 29, protesters at Columbia University, who sparked much of the protests across the nation earlier this month, were being asked to voluntarily disperse after the school's president said it was not able to come to an agreement through negotiations.
Since April 24, "a small group of academic leaders has been in constructive dialogue with student organizers to find a path that would result in the dismantling of the encampment and adherence to University policies going forward. Regretfully, we were not able to come to an agreement," Shafik said in a statement on April 29.
One of the top demands of the protesters, for Columbia to divest from Israel, was flatly denied by the university, according to the statement.
The school asked protesters, who number in the hundreds, to voluntarily disperse, but offered no explanation for what would happen if they did not. The school said it did not "want to deprive thousands of students and their families and friends of a graduation celebration." The school's graduation ceremony is set to be held May 15.
"We urge those in the encampment to voluntarily disperse," Shafik wrote. "We are consulting with a broader group in our community to explore alternative internal options to end this crisis as soon as possible. We will continue to update the community with new developments."
Some protesters who encamped on Columbia University's campus defied the school's order to pack up and leave by 2 p.m. on April 29.
Sueda Polat, a student representative from the protesters' negotiating team, told reporters that the university did not engage in good faith negotiations and failed to meet their demands to divest from Israel.
"It is against the will of the students to disperse. We do not abide by university pressures. We act on the will of the students," she said.
Police were outside of the campus as the deadline approached, but they did not immediately enter after it passed.
"Students are aware of the risk of law enforcement … they know how to come together in that risk," Polat said.
A representative from Columbia University said the school began suspending students who have defied the 2 p.m. deadline to leave the encampment.
Ben Chang, the vice president of the office of public affairs, did not say how many people would be suspended but said those students would not be able to attend classes or graduate.
"Students who agree to leave and sign a form committed to abide by university policies will be allowed to complete the semester," he said.
The school's campus is still closed to anyone who doesn't have a student ID.
Chang reiterated that the negotiations with the groups protesting were being done in good faith until discussions broke down.
"We were hopeful and were disappointed when the student protesters could not reach a consensus in the discussion," he said.
Pro-Palestinian protesters at Columbia University occupied a hall on campus early April 30, hours after school officials ordered the dispersal of a protest encampment.
Videos viewed by ABC News appeared to show protesters creating a barricade with metal chairs outside Hamilton Hall after midnight.
Several were seen in the videos unrolling protest posters from one of the building's balconies.
It was unclear how many demonstrators had occupied the hall, which is on Amsterdam Avenue, although there are estimated to be dozens. The Columbia Spectator, a campus newspaper, reported the people who were inside were working to block the building's exits with tables, chairs and zip-ties.
Columbia University has threatened student protesters with "clear consequences" after protesters occupied a building in an escalating standoff. Students defied a 2 p.m. deadline to disperse Monday. Students occupying the building face expulsion, the university warned.
"We made it very clear yesterday that the work of the University cannot be endlessly interrupted by protesters who violate the rules. Continuing to do so will be met with clear consequences. Protesters have chosen to escalate to an untenable situation—vandalizing property, breaking doors and windows, and blockading entrances—and we are following through with the consequences we outlined yesterday," Columbia said in a statement.
Students who did not commit to the terms Columbia's proposed agreement to vacate the encampment by 2 p.m. Monday have been suspended.
"Those students will be restricted from all academic and recreational spaces and may only access their individual residence. Seniors will be ineligible to graduate," Columbia said.
"This is about responding to the actions of the protesters, not their cause," Columbia said.
The NYPD said today that they will essentially be standing "on the sidelines" amid the ongoing protest at Columbia and will not go onto University property unless authorized to do so, or there is an imminent danger.
At a separate briefing, NYC Mayor Adams said that his office is communicating with Columbia University "probably hourly."
The NYPD will continue to police outside the university, per the university’s request.
"They asked us to come into all of their entry points to monitor that," Adams said.
ABC News' Nadine El-Bawab, Darren Reynolds, Bill Hutchinson, Meredith Deliso and Ahmad Hemingway contributed to the report.