High-profile detentions and visa revocations are putting students on edge, as Trump tightens his squeeze on US schools.

In a stunning blow to international scholars who had hopes of studying in the United States, the Trump administration has revoked hundreds of student visas in nearly every corner of the country as part of a vast immigration crackdown.

Leaders at many colleges learned the legal status of some of their international students had been terminated when they checked a database managed by Homeland Security. In the past, college officials say, visas typically were revoked after schools updated the government when students fell out of status.