U.S. embassies and consulates around the world have been instructed to identify groups of people warranting increased scrutiny in the visa-application process and to screen their social-media accounts.
Secretary of State Rex Tillerson revealed the new requirements in recent diplomatic cables, according to March 24 reports from AP and Reuters, which first reported the news.
The measures do not define which "population sets" are to be targeted, but reviews of social-media accounts of visa applicants are intended for anyone suspected of terrorist ties or of having been in areas controlled by the Islamic State (IS) extremist group.
The AP said the State Department would not comment on the report, though it added that attempts were being made to meet requirements from the administration of President Donald Trump to ensure that "visitor screening and vetting procedures are designed to effectively identify individuals who could pose a threat to the United States."