UPDATE - 5PM:
Traffic nightmares continue following this afternoon's fiery truck crash on the M1 Motorway at Cooranbong.
There's around two hours of southbound delays between Toronto and Morisset.
Drivers heading south are being diverted along Palmers Road.
Otherwise leave the Motorway early at the Newcastle Link Road and take the Pacific Highway through Swansea.
Anyone heading north is being diverted onto the Doyalson Interchange.
It's unclear when the M1 Motorway will reopen - avoid the area.
There's massive delays on the M1 Motorway at Cooranbong following a fiery truck crash.
Two trucks have been engulfed in flames following the accident near the Freemans Drive interchange just before 1pm.
Police say one person remains unaccounted for.
Emergency services are at the scene, with firefighters working on a number of spot fires which have broke out in nearby bushland and spread to around 15 hectares in size.
The motorway is closed between Mandalong and Palmers/Cessnock Roads in both directions, with around 12km of southbound traffic banked up.
Southbound drivers are being diverted via Palmers Road.
While northbound traffic is banked up around 7.5km, with diversions in place at the Mandalong Road exit.
Avoid the area if possible.