Immigration officials from Kyoto, Japan have reported that their biometric system located at the Narita International Airport has detected four individuals since the system’s installation in January that tried to fool the system, according to a Japan Times Online article.

The four who were caught had attempted to alter their fingerprints through surgical removal and stitching or filed down, but were subsequently discovered when secondary facial checks were taken when fingerprint samples were impossible.

The system operates by checking the user’s data with a database of those whom have been deported form the country in the past. Due to reports from the four caught, Japanese officials are worried that the recent attempts at beating their biometric system could be related to an organized human trafficking operation based out of China. Under Japanese law, the biometric system makes checks of travelers’ biometric data if they are sixteen years old or older.

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