The campus chapter of Students for Justice in Palestine publicized the incident on Saturday morning, identifying the substance as “skunk,” a chemical weapon used by the Israel Defense Forces against Palestinians and one that U.S. police departments have reportedly acquired in the past.

“Friday’s event was unsanctioned and violated university policies and procedures which are in place to ensure there is adequate personnel on the ground to keep our community safe,” the spokesperson wrote.

Last semester, the university suspended the student groups Jewish Voice for Peace, or JVP, and SJP for holding an “unauthorized event” (a walkout and art display in support of a ceasefire).

They called for financial transparency from the university, which has a $14 billion endowment, working to mobilize students for a tuition strike to push the administration to divest from companies implicated in Israel’s occupation of Palestine and retaliatory war on Gaza.

“Skunk is liable to cause physical harm, such as intense nausea, vomiting and skin rashes, in addition to any injury resulting from the powerful force of the spray,” the Israeli newspaper Haaretz once reported.

Update: January 22, 2024, 8:43 p.m. ETAfter this article was published, a Columbia administrator notified the student body that the suspected perpetrators of the attack were banned from campus while the law enforcement investigation played out.

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