UPDATE 2PM: All northbound lanes of the M1 Pacific Motorway are now open.
The grass fire is under control and smoke has started to clear.
A grass fire burning near the M1 Pacific Motorway at Cooranbong has closed the northbound road as Rural Fire Service crews work to bring the fire under control.
One of two northbound lanes has reopened after the road was completely closed for a short time around 12.30pm Friday. Both southbound lanes remain open, but drivers have been urged to travel cautiously.
Northbound traffic has been diverted at Mandalong Road, where traffic queues have reached five kilometres, a spokesperson for NSW Transport Management has said.
The fire started to the west of the road near the intersection of the Freemans Drive and the Pacific Motorway. Several RFS crews have responded and are working to bring the blaze under control.
Northbound drivers should expect significant delays.
- The details of this story are developing. It will be updated.
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