Mike Downing, chief security officer of Oak View Group, an advisory board for concert venues including Madison Square Garden in NY and the Forum in Los Angeles, told Rolling Stone magazine a special kiosk was set up at Swift's Rose Bowl show in May.
Taylor Swift is bringing her Reputation tour to Netflix. What they didn't know is that their pictures were quietly being taken and then sent back to a command post in Nashville for analysis.
The stadium does not need to notify ticketholders that they are under surveillance because it is a private company.
Describing themselves as "stans" - otherwise known as stalker fans, many use the term lightly, as a way to show they strongly support the artist.
The internet goes wild after OffSet tweets about missing Cardi B
I have my heart on my sleeve right now, you know what I'm saying?" The same day Cardi posted her video, he tweeted " F**K YALL I MISS CARDI ".
The singer allegedly receives hundreds of death and rape threats regularly from sketchy fans.
Then earlier, in April, Julius Sandrock was arrested outside Taylor's Beverly Hills home, wearing a mask and with a knife in his vehicle.
Daily Star Online have approached a representative for Taylor Swift for comment.
The system being adapted for Taylor's concert followed a break in to her property in NY.
Also in May, Mohammed Jaffar was sentenced to six months in jail and five years' probation having been convicted for burglary after he appeared at Swift's NY home five times in two months. Swift took out a restraining order against him in May.
Facial recognition technology is becoming more prominent around the world.