Dozens of officers in helmets arrived on campus and climbed into the building via a laddered truck through a second-story window.

Handcuffed students were led out and taken away in police vans.

The students had been protesting the high death toll from Israel's war with Hamas in Gaza and vowed to resist any eviction.

The incident is one of many pro-Palestinian demonstrations that have been a challenge for university administrators across the United States to manage.

Columbia University's president, Minouche Shafik, wrote a letter to the New York Police Department requesting help to clear individuals, who are not affiliated with the university, from Hamilton Hall and all campus encampments.

She asked for the police presence to continue until May 17 to prevent the reestablishment of encampments.

The letter was met with criticism on Instagram, where protesters expressed outrage over Shafik's use of the words "care" and "safety." The ongoing protests at Columbia, which have resulted in several hundred arrests, mark the most significant unrest on US college campuses since the Vietnam war protests of the 1960s and 70s.

Protesters at Columbia University have vowed to continue their occupation of Hamilton Hall despite suspensions and expulsion threats.

The White House criticized the seizure of the building, labeling it as "not an example of peaceful protest." The protests, which have spread to universities across the US, have raised concerns over balancing free speech rights with allegations of anti-Semitism and hate.

Protesters have set up tent encampments on campuses from coast to coast.

Protesters at Columbia University have pledged to continue occupying campus until their demands, including divestment from Israel, are met.

The university has refused and threatened expulsion.

At the University of North Carolina at Chapel Hill, police intervened to clear an encampment, detaining some protesters.

At Cal Poly Humboldt, police arrested nearly three dozen protesters who had occupied buildings and closed the campus.

Portland State University closed its campus due to an ongoing incident in the library where around 50 protesters had broken in.

Brown University reached an agreement with student protesters to hold a vote on divesting from Israel in exchange for the removal of their encampment.

This is a significant concession from an elite American university during campus protests.

The UN human rights chief expressed concern over heavy-handed police actions against protesters, emphasizing the importance of freedom of expression and peaceful assembly.

Anti-Semitic language and actions at Columbia University led many Jewish students to fear for their safety.

The Gaza war began on October 7 when Hamas militants launched a surprise attack on Israel, resulting in around 1,170 deaths, primarily civilians, according to Israeli official figures.

Militants also took hostages, with Israel estimating that 129 remain in Gaza, including 34 reportedly dead.

In response, Israel initiated a retaliatory offensive that has resulted in at least 34,535 deaths in Gaza, predominantly women and children, according to the Hamas-controlled territory's health ministry.