There has been no sign of a Dunedin tramper missing in North Otago after a fourth day of searching.
David Palmer, a 53-year-old diabetic, been missing in the Ahuriri Valley since going into the area for what was thought to be a half-day tramp on Saturday.
Volunteers from around the lower South Island joined the search near Lake Hawea on Wednesday. Six search teams of up to 60 volunteers arrived from Central Otago, the Catlins, Twizel, Tekapo, Fairlie and Wanaka.
Police say searchers remain hopeful of finding Mr Palmer and are continuing to put in their best efforts.