MAJOR Crash investigators are seeking information regarding a fatal crash in Baldivis last night.
Police said a maroon Holden Commodore sedan was driven south on Kwinana freeway about 11.50pm when it crashed just north of the Safety Bay Road exit in Baldivis.
The three occupants of the vehicle, an adult male, an adult female and a male infant child all received serious injuries in the crash.
Members of the public stopped to provide emergency first aid until police and St John Ambulance personnel arrived.
The infant child was taken to Rockingham General Hospital before being transferred to Princess Margaret Hospital, however he has since passed away.
The two adults were taken to Royal Perth Hospital.
Police believe the maroon Holden Commodore may have been driving in the Success to Baldivis area prior to the crash and investigators would like to speak to anyone who saw the vehicle in those areas between 10pm and the time of the crash.
Anyone with information regarding the crash should call Crime Stoppers on 1800 333 000.