The new program will start in the Denver passport office and be rolled out across the country over the next several years. All American passports are expected to include RFID chips containing personal information by 2017.

State Department personnel have successfully tested the electronic passports over the past year, said Frank Moss, deputy assistant secretary for passport services.

Moss contended that electronic passports improve security by making it harder to forge or alter official documents. All personal information on the chip must precisely match that in the printed portion of the electronic passport. "In the past, it could have been possible to put a new photo inside [a stolen passport] or find someone who looks like the holder," Moss said.

Additionally, if an electronic passport is stolen, the chip has a unique identifying number that can be tracked by law enforcement agencies worldwide, he said.

Moss said that extra memory space on the RFID chip may be used in the future to store biometric information such as a fingerprint image. However, he said no decision has yet been made on how to use the extra storage space.