The Police national dive squad will on Tuesday morning search a Central Otago lake for a man who has been missing since Saturday.
Mark George Naylor has been missing since Saturday.
Senior Sergeant Ian Kerrisk said his vehicle had been found near the The Blue Lake, at St Bathans, but a ground and lake search had failed to find the Clyde man.
The police stood search staff down overnight but were back on site on Monday morning.
Items of clothing, believed to be Mr Naylor's, had been located at the lake close to where his grey and blue Izuzu Bighorn was found. Mr Kerrisk said it appeared the vehicle had been at The Blue Lake since Saturday evening.
Mr Naylor, who is 178cm tall, of stocky build and who has a beard, was wearing a blue Swandri jersey.
There was hope he would be found alive but that hope was fading as time passed, and there were grave concerns for his wellbeing, Mr Kerrisk said.