A mob of Columbia University and Barnard College students violently stormed a campus building Wednesday afternoon in protest of the expulsion of two Barnard students.

Video footage of the storming of a Barnard campus building, Milbank Hall, shows droves of keffiyeh-clad student radicals shoving their way into a building entrance, physically clashing with at least two outnumbered Barnard security guards. Once inside, the agitators chanted “free Palestine” and “intifada, revolution.”

The expulsions, announced Sunday by Columbia University Apartheid Divest—the Ivy League’s most notorious anti-Semitic student group—stemmed from a January incident in which four student radicals stormed an Israeli history class and targeted Jewish students with anti-Semitic flyers that glorified Hamas, showed a trampled Star of David, and advocated violence. Columbia promptly suspended at least one student protester involved.

One flyer passed out to Jewish students stated, “THE ENEMY WILL NOT SEE TOMORROW,” using an upside-down triangle—a symbol that Hamas uses to denote Israeli targets—to spell “TOMORROW.” The flyer depicted a truck full of Hamas terrorists brandishing RPGs and machine guns.

Another flyer, with the caption “CRUSH ZIONISM,” depicted the Star of David underneath a boot. A third encouraged students to “BURN ZIONISM TO THE GROUND.”

In response, Columbia posted a security guard outside at least one Jewish studies course on Wednesday. The university announced that it “mobilized the Public Safety team to prevent future incidents, including identifying and directing additional resources to classes at increased risk for disruption.”

CUAD and Columbia’s Students for Justice in Palestine chapter were involved in Wednesday’s storming.

A week after the pro-Hamas agitators descended on the Israeli history class, anti-Israel student radicals at Columbia dumped cement into a campus building’s sewage system, deploying tactics they studied months earlier at an event hosted by an anti-Israel student group.