9.30am: The accident site has been cleared and all lanes have been reopened on the M1 Princes Motorway after an earlier accident.
MOUNT OUSLEY: All southbound lanes are open on the M1 Princes Mwy after a 4 vehicle crash. Heavy traffic is easing.— Live Traffic NSW (@LiveTrafficNSW) August 8, 2017
Earlier: Southbound traffic coming down Mt Ousley is banking up following a four-car accident.
The accident happened around 8.15am in the southbound lanes of the M1 Princes Motorway, near the New Mt Pleasant Road overpass.
It is understood the four-car accident has closed the left lane of the road.
At this stage traffic is heavy, and starting to stretch back to the top of Mt Ousley.