The landslide occurred at about 1.30pm this afternoon, about 400m west of Pooh Bear corner.

An Ambulance NSW helicopter searched for signs of trapped vehicles shortly after the slide, but a spokeswoman confirmed they didn’t spot anyone in trouble.

Police have also spoken to drivers who witnessed the land slip, and they didn’t believe there were any cars in front of them at the time.

The highway closed immediately after the incident and police have advised only Nelligen residents should use the road.

The area is still very unstable, and rocks are still "trickling" down every few minutes, Eurobodalla Shire Council’s infrastructure services director Warren Sharpe said.

Mr Sharpe was at the site when he told the Bay Post/Moruya Examiner that a geological expert with the NSW Roads and Maritime Service would inspect the site tomorrow morning.

“That should give it a bit more time to settle down,” he said.

He said the site was still unsafe to inspect as there were rocks still “trickling” every few minutes.

Mr Sharpe said at least a hundred tonnes of debris, including rocks, trees and soil, covered at least 40m of road, which extended back up the hill about another 20m.

“But the existing road is still here and sound, the slip has come from the high side,” he said.

“It’s going to be a matter of a clean-up operation and repairing the road once it’s cleaned up.

“It’s not a pretty sight at the moment.”

He said there would be complete road blocks and road closures set-up while the area’s stability is assessed and the clean-up starts.

“My main concern is to make sure the guys are safe to work. They’ll work over the weekend if we get the clear that it’s safe.”

In the meantime, traffic has been diverted to Nerriga Rd, Braidwood Rd and Turpentine Rd, which links Braidwood to Tomerong, south of Nowra on the Princes Highway.

In the south, motorists have been urged to use the Brown Mountain.