Northbound lanes remain closed at Tyndale crash.
Stop/slow traffic control is in place in the southbound lane allowing one lane of traffic to pass in one direction at a time.
The Pacific Highway has been closed in both directions at Tyndale, north of Grafton.
It follows a 4 vehicle crash at Sheenys Lane just after 2:30pm.
Emergency Services are onsite. The Westpac Life Savers Rescue Helicopter landed at the scene just after 3pm.
According to the Traffic Management Centre, it is understood that a person is trapped in one of the vehicles.
Light vehicles can use South Arm Road and Lawrence Road as a local diversion.
Heavy vehicles should delay journey.
With already heavy holiday traffic on the roads, motorists are encouraged to delay their journeys and can expect significant delays into the afternoon.
It is unknown at this stage how long the highway will be closed.