Columbia University said on Thursday it had doled out a range of punishments to students who occupied a campus building last spring during pro-Palestinian protests, Reuters reports.

Columbia University’s interim president, Katrina Armstrong, has called the administration’s concerns legitimate and said her institution was working with the government to address them. Campus protests and pro-Israel counter-protests have drawn allegations of Islamophobia, anti-Semitism,and racism.

The university said in a statement on Thursday that its “judicial board determined findings and issued sanctions to students ranging from multi-year suspensions, temporary degree revocations, and expulsions related to the occupation of Hamilton Hall last spring.”

The university, citing legal privacy restrictions, did not release the names of students who were disciplined, nor did it say how many students faced punishments, which the students can appeal.

The union representing Columbia student workers, UAW Local 2710, said in a written statement that its president, Grant Miner, was among the students expelled, just one day before contract negotiations with the university were set to begin, a move the union called “the latest assault on First Amendment rights …”

A university spokesperson said they had no comment on the union statement. Columbia was the epicenter of protests against Israel’s invasion of Gaza that hit several US college campuses.