Among the thousands of evacuees who successfully attempted their narrow escape from Afghanistan, were nearly 100 individuals flagged for potential ties with terrorists, a recent report estimates.

Although it still had to leave thousands of legitimate evacuees behind, more than 30,000 thousand individuals had been rescued, according to NBC News, and precaution measures had required a third of them to undergo additional background checks.

Noting that federal officials were taking abundant caution, the news media said among those 10,000 refugees, approximately 100 people were flagged for potential terrorist ties.

A person could be flagged simply for their name or a single suspicious number in their cell phone, NBC News said. The person then would be immediately barred from entering the U.S., and have to wait for further review of their profile.

“Some of the vetting occurs while they are overseas, and some of it occurs here,” said a senior federal law enforcement official. “… We are not going to allow people to intentionally be released into the community if they have unresolved derogatory information.”

At least two people who boarded at a U.S. airport were going to be redirected to Kosovo for security concerns. The country had become a destination to host individuals who failed to clear initial rounds of screening or whose cases otherwise require more time.

The Associated Press last week reported that Kosovo had agreed to provide temporary shelters for Afghan evacuees on the U.S.’s behalf, and they could remain in the country for up to a year.

Other countries that the refugees would be vetted before entering the U.S. include Qatar, Bahrain, Kuwait, Italy, Spain, and Germany, and others. 

Even if they passed the third country checks, additional background screening upon arrival in the U.S. is still compulsory before deplaning.

Likewise, some individuals who were deported for criminal offenses were detected among the refugees being vetted in D.C., sources told NBC News. The Department of Homeland Security (DHS) was looking at how to deal with them.

Secretary Alejandro Mayorkas of DHS said they had blocked individuals on terror watchlists from entering the U.S., but he did not give any details about how many of them. 

Meanwhile, a senior State Department official confirmed that a majority of Afghans granted special visas were left stranded in Afghanistan after August 31. On Tuesday, White House Press Secretary Jen Psaki estimated that there are still 100 to 200 American civilians in Afghanistan who want to leave.