American Airlines is now using facial recognition to board passengers on the carrier's international flights out of DFW International Airport.

The technology matches a scan of the passenger's face taken at the gate with a passport photo on file with U.S. Customs and Border Protection.

American tested the program last year on select flights and will begin to roll out the facial recognition in full, American said Tuesday.

Facial scans will replace boarding passes for getting on American's international flights, although customers will still need a physical or digital boarding pass to get through TSA security lines. They will also need their passports to clear security.

"Facial recognition makes the process for verifying the identity of travelers more efficient, accurate and secure," said a statement from Judson W. Murdock II, director of CBP's Houston office. "This technology also enhances the boarding process for international flights, which is a win-win for airlines and travelers."

American said it will not store any photos.

Gate agent Erica Shin assists as passengers board an American Airlines flight to Tokyo Narita International Airport using facial biometric scanning Tuesday, Aug. 27, 2019 in Terminal D of DFW Airport. The iPad device, which is currently only in use for international travelers, matches faces with the U.S. Customs and Border Protection (CBP) database, which includes passport photos. The information collected is transmitted only to CBP and not to independent airlines. (Ryan Michalesko / Staff Photographer)

For now, facial-recognition boarding will be available only on a handful of international flights in Terminal D, but American plans to expand it to 75 gates in Terminals A, B, C and D by the end of the year.

Emirates Airlines also started using a facial-recognition scan on flights from DFW Airport to Dubai in July.

Facial recognition is becoming a growing part of airport security. CBP is ramping up its biometric exit program, which aims to identify and track passengers leaving and entering the United States.

American started using the technology at Los Angeles International Airport in December. Delta Air Lines is using it for international passengers at a handful of airports, including Atlanta's Hartfield-Jackson, Salt Lake City and Minneapolis.

If the technology does not match a face scan to photos, gate agents are still allowed to use other methods to board passengers.