India, April 14 -- A hi-tech facial recognition system that has improved visitor screening at Mantralaya and curbed footfalls has thrown up an unexpected challenge - over 10,000 visitors have failed to return their RFID entry passes, a key component of the security set-up.

The new system was rolled out in phases from January last year following complaints about unauthorised visitors entering the state secretariat. After a visitor is screened for facial recognition, an RFID card stores data relating to their identity as well as personal details, the purpose of their visit, departments they intend to visit, among other things. An RFID pass is then issued, containing the data thus captured as well as tracking features.

Visitors are require...