Jessica O'Connor and Dion Reynolds, both 23 and from the Tasman area, started out on May 9 into the rugged wildnerness of the Kahurangi National Park, but haven't yet returned.
They were understood to have entered the Anatori River car park, which was in a remote part of western Golden Bay.
Senior Constable Dave Cogger said police would begin using a defence force NH90 helicopter and crew in tonight's search for the pair.
He said 14 were involved in today's search, supported by a drone with infrared capabilities, and a team of three would search overnight.
Police said today's search did find footprints at an historic campsite near the Webb River but they had not yet been able to confirm if either the footprints or the campsite belonged to the pair.
The NH90 helicopter with a crew of four and a medic on board would search inland from the Anatori river mouth. Crew would be using night vision goggles to look for light sources, such as fires or torches, which might be being used by the trampers.
Cogger was coordinating the search from the Richmond Emergency Operations Centre. He said the searchers were being helped by Fire and Emergency New Zealand's command vehicle placed near the Anatori car park.
"That's enabled us to link straight into the Richmond emergency centre. We've also had a very generous farmer who's allowed us to use his broadband connection and we've put a repeater station up there to enable us to talk to the teams in the field."
Cogger would not comment on the fact the pair had gone hiking during alert level 3 lockdown, which restricted tramping to short-duration day hikes in locations near to where people lived.
"To be fair, that's not something we're concentrating on. Our focus is on bringing back Jess and Dion."
Cogger said, from the information they had on the pair, including that from family, friends and employers, no one had raised any doubts about O'Connor's competency in the outdoors.
"With good skills, good preparation, good gear and with the amount of food they took in with them - or alleged to have been taken in with them, their survivability is high."
Cogger said the police still had no idea of the pair' intentions.
"Despite our large media canvas, having a lot of police staff working in Golden Bay and a police communications system with lines open, we still don't have any concrete idea of where they were going and when they were due out."
Cogger said every effort was being made to find the pair, and police were offering support to their families.
"We're in regular contact with the families who are being updated by the police, and who are being supported by services provided by Victim Support."
Police said they would continue to search until all avenues were exhausted.
