Snowden: NSA intercepting millions of online facial images every day

The National Security Agency (NSA) is processing large numbers of images for use in its facial recognition programs, according to documents obtained from Edward Snowden.

As the number of images in emails, social media and other communications continues to grow, the NSA has come to rely increasingly on facial recognition tech in recent years.

According to 2011 documents, the NSA intercepts "millions of images per day", of which roughly 55,000 are "facial recognition quality images." The agency claims that facial images, fingerprints and other identifiers are becoming just as important as the more traditional written and oral communications.

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The top-secret information claims that the NSA is taking a "full-arsenal approach" to compile "biographic and biometric information" of its targets. A 2011 NSA PowerPoint presentation included in the documents shows several photographs of an unidentified man alongside information including his passport, visa status and suspected terrorist ties.

The images are likely to focus on foreign nationals, given that the NSA must gain court approval to intercept images of US citizens, but the extent of the agency's surveillance is still unclear. Alessandro Acquisti, a facial recognition researcher at Carnegie Mellon University stated, "Facial recognition can be very invasive. There are still technical limitations on it, but the computational power keeps growing, and the databases keep growing, and the algorithms keep improving."

This is mirrored by state and local law enforcement, who already utilise a wide range of facial imagery, such as driver's licenses and Facebook, to identify their suspects. The FBI is also building its own "next generation identification" project that looks to combine facial imagery with fingerprint identification and other biometric information.

Read more: Avoiding facial recognition of the future

NSA spokeswoman Vanee Vines said, "We would not be doing our job if we didn't seek ways to continuously improve the precision of signals intelligence activities," in a statement that is unlikely to placate those concerned about the erosion of privacy online.