New York City police arrested dozens of masked protesters on Columbia University’s campus Wednesday evening after they took over part of a central library while students were trying to study for final exams.

Over 100 demonstrators crowded a Columbia University library reading room Wednesday, prompting school administrators to call on the New York Police Department to quell the protest. The NYPD told POLITICO that “multiple” arrests had been made,

Protests at Columbia University resulted in the NYPD taking dozens of people into custody Wednesday at Butler Library on campus.