A passenger information system, PIS, for a public transport vehicle comprises a public compartment and a restricted compartment. The PIS comprises i) a passenger information terminal for communicating information to users when located in the public compartment; and ii) a first electronic identification device configured to receive an electronic identification from an operator when located in the restricted compartment and to register the electronic identification with the PIS as a registered electronic identification; and iii) an interfacing system comprising inputting means for inputting information into the PIS. A second electronic identification device is configured to receive an electronic identification from a user of the interfacing system. The PIS is arranged to authorize the inputting of information when the electronic identification from the user matches the registered electronic identification.