An intensive search for a tramper in the Wilkin River area of Mount Aspiring National Park has so far failed to find the missing man.
Two volunteer search and rescue teams from Wanaka returned to base this evening after a day-long search of a difficult gorge area but had no luck.
Wanaka Police SAR coordinator Sergeant Aaron Nicholson said the search teams would be thoroughly debriefed before deciding on what to do next.
But he said he believed the missing man had not gone beyond the area of the gorge and the flats directly below it.
Wanaka Search and Rescue management team member Phil Melchior said downstream from the gorge were shallow river flats which become four shallow strands.
"He decided that he would see if he could take a short cut through the gorge and follow the river rather than climb up the track that goes well above the river and back down again - we're not sure what happened after that."
The man, whose name has not been released, was last seen at 6.30pm on Sunday when he parted with other members of his party to try and negotiate a shortcut back to his campsite.
The terrain in this area is extremely difficult and search teams said they had fears for the man's safety.