WASHINGTON (AP) — A bipartisan group of senators wants restrictions on the use of facial recognition technology by the Transportation Security Administration.

The lawmakers say they’re concerned about travelers’ privacy and civil liberties.

In a letter Thursday, 14 lawmakers are calling on Senate leaders to use the upcoming reauthorization of the Federal Aviation Administration to limit use of the technology so Congress can put in place some oversight.

TSA has been rolling out the technology at select airports in a pilot project.

The agency says the system improves accuracy of identity verification without slowing passenger speeds at checkpoints.

Passengers can opt out.

The TSA says photos and IDs are deleted after the passenger goes through the checkpoint.