At a press conference in Wellington this afternoon, Inspector Mike Wright said the cost of the search could have been up to $50,000.
"More of a concern than the terms of cost is the emotional cost to the family of Mr Smithies and to the searchers who have turned out. Many of those are people on holiday, given the time of the year, so they've given up their own personal time."
Police have referred him to medical specialists, suggesting he is of a delicate mental state.
When asked about the reason why he had hit the road, police said that was a matter between Mr Smithies and his family.
He had shown up at Clive disorientated and distressed, police said.
He was remorseful and quite traumatised, and remained with medical professionals.
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