5:08pm: Southbound motorists are still experiencing major traffic delays following a truck accident on the M1 Princes Motorway five kilometres south of Helensburgh on Saturday afternoon.

Emergency crews were called to the scene just after 3.30pm after reports a truck towing a trailer with a car on it had jack knifed and overturned and the car had caught on fire.

An ambulance spokesperson said the driver suffered only minor injuries. Fire crews attended to extinguish the fire.

The accident site has now been cleared but Live Traffic advises that there are heavy traffic conditions southbound and motorists should expect significant delays.