Columbia is investigating reports that protesters were sprayed with chemicals

Columbia University and the New York Police Department are investigating reports that pro-Palestinian student protesters were sprayed with a foul-smelling chemical at an event last week, prompting the university on Monday to ban the accused from campus.

In a statement emailed Monday evening to all students and faculty at Columbia and Barnard College, Dennis A. Mitchell, the university's interim provost, said the individuals had been expelled while police investigated “what appear to be serious crimes been'. , possibly hate crimes.”

He called the events at the protest, on the steps of Low Library, “deeply disturbing” and added that the university condemned “in the strongest possible terms any threats or acts of violence” against its community members.

A police spokesperson said no arrests had been made and investigations were continuing.

Columbia's statement did not say how many people were barred from campus or whether they were students. It did not specify what substance was sprayed on the protesters, what led to the incident or whether anyone needed medical attention.

Since the war between Israel and Hamas began in October, pro-Palestinian and pro-Israel demonstrations have roiled Columbia and other American universities. Although the demonstrations were largely peaceful, some acts turned to intimidation or violence. In October, an Israeli student was attacked by a fellow student in Columbia after putting up hostage posters.

Pro-Palestinian students at Columbia have been threatened online and had their faces and names displayed on a truck funded by an outside group that labeled them anti-Semites.

In an effort to defuse tensions on campus, Columbia President Minouche Shafik suspended two pro-Palestinian student groups, Students for Justice in Palestine and Jewish Voice for Peace, in November. The university said the groups had broken rules for student events by repeatedly failing to ask for permission long before protesting. The groups pushed back, calling the rules unjust, and joined a coalition that continued to organize protests under different banners.

A Columbia University official said Friday's events were unsanctioned and violated university policy.

According to a Barnard student who was at the protest Friday, people from the two suspended groups were involved in the demonstration at the Low Library and were protesting peacefully when at least two men sprayed them with a foul-smelling liquid.

“We started smelling this horrible smell halfway through the protest,” said Maryam Iqbal, an 18-year-old freshman at Barnard. “I can only describe it as raw sewage and dead mice.”

Layla Saliba, a 24-year-old Palestinian-American student at the Columbia School of Social Work, said two men, whom she did not recognize, looked as if they had wanted a confrontation and called some protesters “terrorists.” She added that they seemed “particularly aggressive” toward students who held up signs reading “Jews for a Ceasefire” and calling them “self-hating Jews.”

She said Monday that she continued to vomit and still smelled her clothes and hair, even after nearly a dozen showers.

On Sunday, Ms. Iqbal said she reported the incident to the Columbia Department of Public Safety and showed staff there a jacket she wore at the protest as evidence. But she said when she smelled the jacket, she felt nauseous and was treated at a hospital for nausea.

In its statement, Columbia asked anyone with photos, videos or other evidence of the event to share them with police.

Sharon Otterman And Chelsia Rose Marcius reporting contributed.