The US institution says it has banned attackers responsible for spraying a dangerous chemical at a pro-Palestine rally.

Columbia University has banned several people accused of spraying pro-Palestinian protesters with a foul-smelling chemical during a demonstration, the New York-based institution said.

In a statement emailed to Columbia University students and faculty members Monday evening, Interim Provost Dennis A. Mitchell said the alleged perpetrators had been banned from campus for “obviously serious crimes, possibly hate crimes.”

“The university received additional information on Sunday evening. “As a result, the suspected perpetrators identified to the university have been immediately banned from campus while law enforcement investigations continue,” Mitchell wrote, according to US media outlet Rolling Stone.

Mitchell said the university “strongly condemns any threats or acts of violence” directed at its community and described the incident as “deeply disturbing.”

Columbia has asked anyone in possession of photos, videos or other evidence of the event to provide them to police.

The university did not make it clear whether those excluded were students or how many people were involved.

The Columbia Spectator, a student newspaper, reported that protesters were attacked on the steps of Low Library on Friday during a “Divestment Now” rally. At least three students required medical attention, while others reported physical symptoms such as burning eyes, headaches and nausea.

A police spokesman told the New York Times that there had been no arrests.

According to 18-year-old college freshman Maryam Iqbal, who was interviewed by Rolling Stone, peaceful protesters were sprayed with a foul-smelling liquid by at least two men.

Another student, Layla Saliba, a 24-year-old Palestinian American, said the two men called some of the protesters “terrorists.” She added that they were “particularly aggressive” toward students who held signs reading “Jews for Armistice,” calling them “self-hating Jews.”

Saliba told American magazine that she was constantly vomiting and could still smell the smell after a dozen showers.

tensions have increased at some American universities since the Palestinian group Hamas launched a surprise attack on Israel on October 7 and Israel responded with a statement War.

Members of the Jewish anti-Zionist organization Jewish Voice for Peace have reported being spat on and harassed on campus because of their views.

Omar Shakir, Human Rights Watch’s (HRW) director for Israel and Palestine, said a speaking agreement was canceled twice by the US university due to a lack of “security clearances”.

The Ivy League institution suspended student groups Students for Justice in Palestine and Jewish Voice for Peace in November for alleged violations of school policies involving “threatening rhetoric and intimidation.”