Clothing and a shoe were found approximately 150m north of the fire.
Today 40 search and rescue volunteers have travelled from as far as Tauranga and Whanganui and will continue the intensive search in 10 teams of four. Because of poor weather a helicopter is unable to help.
The search will focus on the area radiating out from where the campfire and clothing was found.
Police believe the two men would now be in a very serious condition, likely suffering from hypothermia.
Inspector Kevin Taylor said the search teams would remain in the bush for the day.
"The bush is exceptionally dense and this is a challenging search.
"If the two individuals are not responsive, they will only be found once a searcher is in their immediate vicinity," he said.
"The longer these young men remain in these conditions, the less likely it is that they will survive."
Taylor said they remained determined and hopeful they would find them alive.
Further updates on the search will be released as they become available.