Search resumes for trampers missing for almost two weeks at Kahurangi National Park

Jessica O'Connor (left) and Dion Reynolds, both 23, have not been seen or heard from since going on a tramp at the Kahurangi National Park on May 9. Photos / Supplied

More resources are being brought in to help in the search for two trampers who have now been missing for almost two weeks.

Jessica O'Connor and Dion Reynolds, both 23, were last seen or heard from on Saturday, May 9, when they set off on a tramp in the Kahurangi National Park, in the Nelson Tasman region.

Police said this morning that an NH90 helicopter would continue to deploy search teams and install more radio repeater stations at the site.

A search is also being planned near the Anatori River catchment, a police spokeswoman said.

"Both ground and air searchers commented on the density of the bush, which makes searching difficult," she said.

Three search teams who worked overnight have been rotated out for three fresh teams who are due to be doing what was described as "more detailed" searches into the hills today.

A search dog was also part of the teams overnight and has been swapped out also.

'Number of searchers to grow today'

Extra fuel for the helicopter is being trucked down to a spot at the Anatori River.

Police said two search teams were winched into the headwaters - near The Fosters Lookout - late last night and would be searching downhill towards the river today.

"The number of searchers involved is expected to grow throughout the day."

As well as having people on the ground, authorities are also a USAR drone that is searching the wider area for detection of heat or light.

Yesterday, search teams came across footprints and a historic campsite near the Webb River.

However, it is not yet known whether either belong to the missing pair.

Authorities are also working to work out differing reports of the expected return of the pair.

"Police are asking for anyone who has been around the Anatori, Webb, Kokopu, Independent and Fraser rivers since May 8 and who may have seen the pair to get in touch."

Can you help? Call Police on 105 and quote the event number: P042228949