The U.S. State Department said on Monday it has cancelled more than 6,000 foreign student visas since 20 January, citing overstays, criminal offences and, in a minority of cases, alleged support for terrorism. The figure represents one of the most aggressive single-year actions against student visa holders in recent memory. A senior department official told reporters that roughly 4,000 visas were withdrawn after holders were charged with crimes such as assault, driving under the influence and burglary. An additional 200-to-300 students lost their visas for what officials described as links to or advocacy for terrorist organisations; the remainder were removed for violating the terms of their stays. Secretary of State Marco Rubio has ordered U.S. embassies to apply expanded social-media vetting and to scrutinise applicants deemed hostile to American interests, especially in the wake of campus protests over the Gaza war. The official added that total visa revocations of all types this year now stand at about 40,000, compared with 16,000 during the same period of the prior administration. The Trump administration argues the measures protect national security and campus safety. Civil-liberties groups and several universities counter that the sweep risks violating free-speech and due-process rights, setting the stage for potential legal challenges as the academic year begins.