Handling of integrity check failure in a wireless communication system can safely send the mobile station to the idle mode upon detection of security failure. Alternatively or in addition, attempts to recover from the security failure situation can be enabled without forcing the mobile station to enter idle mode. The mobile station autonomously transitions to idle mode when the integrity check failure is detected a certain threshold number `X` times during a specified period `Y`. Whereupon, the mobile station initiates the Radio Resource Control (RRC) connection re-establishment procedure after integrity check failure is detected. In the RRC connection re-establishment procedure, the security parameters are re-initialized to provide a possibility to recover from the failure situation.