Meanwhile, bank and telephone records are being closely examined by investigators trying to piece together what has happened. Earlier attempts to retrieve his banking details from England had been delayed due to Christmas holidays.
''[H]is banking literature is on his laptop, which is locked and is flat,'' Senior Constable David Cogger said yesterday.
Mr Wyatt arrived in New Zealand in November with the intention of walking the Te Araroa Trail which links tramping routes from Cape Reinga to Bluff.
He has not been in contact with his parents in Cornwall, England, since December 12.
Police say there are "very keen'' to speak to anyone who was tramping in the Blue Lake, Sabine Valley, D'Urville Valley area of Nelson Lakes National Park between December 13 and 19.
Mr Wyatt is 6ft 1in tall, with ginger hair and was carrying light equipment.
Anyone with any information is asked to contact Nelson police on 03 546 3840.