9.06am: All southbound lanes have now been reopened. The Traffic Management Centre said traffic is still heavy but should clear soon.
9am: Southbound traffic is now banked back almost five kilometres, nearing the southern end of the Big Dipper.
8.54am: Traffic heading north appears to be easing following the removal of the broken-down truck.
Traffic had been banking up as far back as the University of Wollongong but the queues are now shorter.
8.52am: The accident is also causing problems for motorists on Picton Road trying to merge onto the M1.
There is heavy traffic along the Picton Road overpass.
8.41pm: Southbound traffic on the M1 Princes Motorway is now backed up almost to the Picton Road overpass.
8.36am: The three-car accident was a “nose-to-tail” accident. The driver of a ute, who was caught in between the two other cars, is still in his vehicle.
Fire crews have removed all the doors and ambulance officers are preparing to extricate him from the ute.
It is understood that, while he is not trapped, the driver has reported tingling in his legs.
8.33am: There are reports that the broken-down truck has been removed from lane one northbound on the M1 Princes Motorway.
8.30am: Two lanes of northbound traffic are now closed. The left lane is closed due to the broken-down truck, while the right lane is also closed to allow for emergency vehicles assisting with the accident.
Northbound traffic is now banked back to the bottom of Mt Ousley.
8.29am: Southbound traffic is is banking up now and is heavy almost to the Picton Road off ramp.
8.15am: An accident and a breakdown are causing traffic problems in both directions on Mt Ousley.
Both incidents have occurred in the vicinity of the New Mt Pleasant Road overpass.
On the southbound side of the M1 Princes Motorway directly under the overpass, emergency services are dealing with a three-car accident.
Initial reports were that one of the drivers was trapped in their car but this is no longer the case.
Traffic heading down the mountain is starting to bank up.
Meanwhile, on the northbound side of the highway, a broken-down truck has blocked off one lane of the M1.
The breakdown is just north of the overpass and traffic is heavy down the mountain.