Police are using software to scan the sands of Virginia Beach for criminals and missing persons to keep residents and tourists safe.

The coastal city is using three cameras to scan a four-block area of beachfront property. The cameras feed images directly to police station monitors, where software automatically checks faces on the screen against mugshots in a database.

The system will alert police to a possible match. If an officer decides the faces are similar, an officer on the street will be asked to check the match in person.

Critics say the project is an invasion of privacy and that the software is inaccurate. But advocates say facial recognition is a useful tool that shouldn’t scare anyone who has noth-ing to hide.

An advisory board made of members of various organizations helped create guidelines to avoid abuse of the system and will continue to conduct periodic audits.