The Railway Ministry on Thursday ordered that Aadhaar number has been made mandatory for senior citizens to avail concessions in train tickets from April 1. An official from the ministry also added that the Aadhaar number must be used for one-time registration at the IRCTC ticketing site. Further, he added that Indian Railways would soon transition onto  Aadhaar-based online ticketing system to prevent touts from blocking a bulk of tickets, end fraudulent bookings and impersonation.