A mobile security system for use in an automobile or other vehicle, which activates a cellular phone to automatically dial an emergency telephone number and plays a voice recording including position information provided by the vehicle operator. The vehicle operator is prompted to record new position information when the vehicle ignition is turned off. The system can be remotely activated by a wireless transmitter device which generates an RF signal when a "panic button" is depressed. Components of the security system include a cellular telephone, RF receiver device, recording device, and controller. A speaker and microphone permit two-way communication between the vehicle operator and emergency personnel.