The dogs were on the scene for much of Tuesday but were unable to find any signs of Mr Ross.

Leading Senior Constable David Cole and Sergeant Roger Mayer of the NSW State Protection Group dog unit in Sydney began the search with the dogs at 9.30am and in the next six hours scanned the roadside and scrub.

The two officers and dogs moved through eight kilometres of road either side of the base and approximately five square kilometres of bushland.

Glen Innes Inspector George McGilvray said this was the earliest suitable time where search dogs would be of use in this situation.

“The advice given to us by the dog unit when the car was first found was that they would not be able to track him so long after he had gone missing,” he said.

The cadaver dogs differ from tracking dogs in that they are trained to pick up the smell of decomposing bodies not the scent of a person.