The move appears to be a significant expansion of a process previously focused on students involved in pro-Palestinian activity

The US State Department said on Thursday that it was reviewing the records of more than 55 million foreigners who hold valid US visas for potential revocation or deportable violations of immigration rules.

In a written answer to a question posed by Associated Press, the department said that all US visa holders are subject to “continuous vetting” with an eye towards any indication that they could be ineligible for the document.

Should such information be found, the visa will be revoked and, if the visa holder is in the United States, he or she would be subject to deportation.

The department said it was looking for indicators of ineligibility, including visa overstays, criminal activity, threats to public safety, engaging in any form of terrorist activity, or providing support to a terrorist organisation.