Even as it fends off a flurry of legal challenges against the travel ban, the Trump administration isn’t letting up on its plans to implement “extreme vetting” of newcomers to the United States.

In a series of diplomatic memos issued during the past two weeks, Secretary of State Rex Tillerson has ordered U.S. consular officials to identify “populations warranting increased scrutiny” and subject them to a tighter visa screening process.

According to Reuters, which first reported on the memos Thursday, Tillerson has also called for “a mandatory social media check” for all visa applicants who have ever been in territory controlled by the Islamic State.

Two of Tillerson’s memos outline how to implement President Donald Trump’s revised executive order on immigration, but some of the guidelines have been rescinded after a Hawaii judge issued a temporary injunction to block key parts of the travel ban from taking effect March 16.

It’s unclear how the new screening process will affect Hawaii’s $15 billion tourism industry, which had 8.7 million visitors — including 6,800 from Middle East and 2,000 from Africa — in 2015.

But Tillerson’s memos are already under fire from some critics, who are voicing concerns over the prospect of profiling.

Jay Gairson, a Seattle-based immigration attorney, told Reuters that “what this language effectively does is give the consular posts permission to step away from the focused factors they have spent years developing and revising and instead broaden the search to large groups based on gross factors such as nationality and religion.”

“All visa decisions are national security decisions.” — Secretary of State Rex Tillerson

Others say that the social media checks, which are rarely performed by consular officials, will add another bureaucratic layer to an existing screening process that’s already lengthy and difficult to follow.

Tillerson’s memos appear to anticipate some delays, noting that the new screening process “may cause interview appointment backlogs to rise,” and urge consular officials to reduce the number of visa interviews each day.

Still, Tillerson argues that the new screening process is necessary for national security.

“All visa decisions are national security decisions,” Tillerson wrote. “Consular officers should not hesitate to refuse any case presenting security concerns.”