More than 175,000 visas held by foreign nationals have been revoked since President Donald Trump returned to office, citing criminal activity, visa violations, fraud, calls for violence against Americans, and other threats to national security.

The State Department announced the figure on Monday, marking a sharp escalation in the administration’s immigration enforcement efforts.

State Department spokesperson Tommy Pigott said the revocations target foreigners who “violated the terms of their visas, committed crimes, called for violence against US citizens, defrauded Americans, abused our immigration system, or endangered national security.”

Most visas were revoked following law enforcement encounters, with assault, driving under the influence, theft, and drug crimes among the leading causes.

The department said in January that it had revoked more than 100,000 visas, which was a record at the time.

Secretary of State Marco Rubio said last month the State Department, under his direction, revoked more than 300 visas, with most of those being student visas.

The latest figures show a sharp spike in visa cancellations year-over-year.