Bushwalkers missing on NSW Central Coast

Up to three people are missing after they failed to return from a bushwalk in the NSW Central Coast hinterland.

The alarm was raised at a farm at Mangrove Mountain about 6.30pm on Friday after up to three people failed to return from a walk.

A police spokesman says a command post has been set up at the farm.

A Westpac Rescue Helicopter spokesman says a crew left about 9pm to join the search for three bushwalkers who had been due back about 4pm.