Hundreds of students’ visas have been revoked. In a few cases, the Trump administration has sought to deport them because of their pro-Palestinian activism, citing national security.

University of Chicago officials said Wednesday that the visa terminations of three students and four recent graduates were found during an audit. International students at the University of Illinois and Northwestern have also reportedly had their visas revoked.

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.