by Al Jazeera Staff and ReutersThe US State Department has revoked more than 175,000 visas from foreign nationals under President Donald Trump, as it continues a sweeping immigration crackdown that has stripped travel and immigration privileges from tens of thousands more people. Most of the visa revocations stemmed from law-enforcement encounters involving criminal activity, alongside visa violations, fraud, calls for violence and other threats to national security, according to a fact sheet released by the department on Monday. The department said the Trump administration would continue identifying and investigating foreign nationals who it believes threaten US safety or national security. In January, the department said it had revoked more than 100,000 visas, a record at the time. The administration has also adopted a stricter policy on granting visas, with tightened social media vetting and expanded screening.