A fingerprint is now required for season pass holders at Six Flags St. Louis.

The St. Louis Post-Dispatch reports that a measurement of the fingerprint will be attached to a bar code on the plastic card to get into the park. Pass holders at the entrance will have to scan both the card and his or her finger to get in. Six Flags began the system more than a week ago when the park reopened for the 2014 season.

The technology known as biometrics has been in use in some other amusement parks such as Disney World and Universal Studios. A Six Flags spokeswoman says that, eventually, it will be at all Six Flags parks across the country.

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