More than 600 international students and recent graduates in the US have had their visas revoked or their legal status changed by the state department, according to data aggregated from around the country.

The data, collected by Inside Higher Ed, shows that as of Thursday more than 100 colleges and universities have identified more than 600 cases of students whose immigration status was changed by the Trump administration. These institutions say that their students have lost their F-1 or J-1 student visas.

Some of these cases were related to their activism and participation in student-led protests against the war in Gaza, and others were for “minor crimes”. Inside Higher Ed says that the majority of college officials say they’re unsure why the foreign-born students had their visas revoked or have yet to receive formal notification of the changes. Most have still not received any communications from immigration authorities.