6. The decryption system according to claim 1 wherein the user identity document data comprises one or more of a user identity document number, an expiry date of the user identity document and a date of birth of the user.
1. A decryption system for decrypting user information encrypted on a storage device associated with an identity document of a user, the system comprising: a server configured to collect user identity document data from the user and to construct a token comprising the user identity document data; a mobile device comprising a reader configured to read the user identity document data from the token by radio frequency identification communication, wherein the reader uses the user identity document data read from the token to decrypt the user information stored on said storage device and wherein the reader is further configured to read, by radio frequency identification communication, a user identity document biometric facial image from said storage device using the user identity document data; a camera configured to capture an image of the user's face; a comparator configured to compare the captured image of the user's face with the user identity document biometric facial image read from the user identity document; and authentication means for authenticating the user depending upon the result of the comparison.