(CNET) – What if a stranger could snap your picture on the sidewalk then use an app to quickly discover your name, address and other details? A startup called Clearview AI has made that possible, and its app is currently being used by hundreds of law enforcement agencies in the US, including the FBI, says a Saturday report in The New York Times.

The app, says the Times, works by comparing a photo to a database of more than 3 billion pictures that Clearview says it’s scraped off Facebook, Venmo, YouTube and other sites. It then serves up matches, along with links to the sites where those database photos originally appeared. A name might easily be unearthed, and from there other info could be dug up online.

The size of the Clearview database dwarfs others in use by law enforcement. The FBI’s own database, which taps passport and driver’s license photos, is one of the largest, with over 641 million images of US citizens. The Clearview app isn’t currently available to the public, but the Times says police officers and Clearview investors think it will be in the future. FULL REPORT