Migrants lacking passports must now submit to facial recognition to board flights in U.S.

The U.S. government has started requiring migrants without passports to submit to facial recognition technology to take domestic flights under a change that prompted confusion this week among immigrants and advocacy groups in Texas.

The U.S. government has started requiring migrants without passports to submit to facial recognition technology to take domestic flights under a change that prompted confusion this week among immigrants and advocacy groups in Texas.

It is not clear exactly when the change took effect, but several migrants with flights out of South Texas on Tuesday told advocacy groups that they thought they were being turned away. The migrants included people who had used the government's online appointment system to pursue their immigration cases. Advocates were also concerned about migrants who had crossed the U.S.-Mexico border illegally before being processed by Border Patrol agents and released to pursue their immigration cases.

The Transportation Security Administration told The Associated Press on Thursday that migrants without proper photo identification who want to board flights must submit to facial recognition technology to verify their identity using Department of Homeland Security records.

"If TSA cannot match their identity to DHS records, they will also be denied entry into the secure areas of the airport and will be denied boarding,” the agency said.

Agency officials did not say when TSA made the change, only that it was recent and not in response to a specific security threat.

It's not clear how many migrants might be affected. Some have foreign passports.

Migrants and strained communities on the U.S.-Mexico border have become increasingly dependent on airlines to get people to other cities where they have friends and family and where Border Patrol often orders them to go to proceed with their immigration claims.