Search teams were still scouring rugged bush in Kahurangi National Park, west of Motueka, last night, as the hunt for a man missing for 10 days escalated.
Eighteen searchers in teams of three were supported by a helicopter yesterday.
An Air Force Iroquois and more searchers were expected to enter the search area from first light today.
Constable Mike Parfitt said the alarm was raised when Department of Conservation staff found abandoned clothes and a note from the tramper, Karl Ezra Sorensen, 23, in the bush near the headwaters of the remote Leslie River on Tuesday.
The note was found in a rugged area away from tracks and said he was injured and intended to walk out, heading north.
Searchers began scouring bush and visiting huts in the area yesterday.
Police and search and rescue teams were assisted by two German shepherd sniffer dogs, trained to sniff the air rather than for specific tracks, Constable Parfitt said.
The weather in the area was good but overnight temperatures were low. Constable Parfitt described the search area as "tiger country."
However, the area was popular with trampers and had a very good network of huts and tracks.
Constable Parfitt said many people used the park, and Mr Sorensen would probably have been found if he had made it to a track.
"If he was fit and able, he would have come across many tracks and many walkers and we believe we would have heard from him," he said.
A man who gave Mr Sorensen a lift into the park on May 17 told police the tramper said he intended to return three days later.
Earlier this year Mr Sorensen had been living in a Nelson flat, provided by a trust which supports people with mental illness.
Constable Parfitt said police had questioned staff, but he refused to comment on Mr Sorensen's connection with the trust.
Police believed Mr Sorensen was not an experienced tramper but had attended outdoor pursuits courses.NZPA
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