Extra resources will assist in the search for missing trampers Jessica O'Connor and Dion Reynolds today.

No heat or light sources were found by the Royal New Zealand Air Force NH90 helicopter that searched inland from the Anatori River mouth overnight.

The NH90 helicopter will continue to deploy search teams and install more radio repeater stations and search the Anatori River catchment.

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

Extra fuel for NH90 is being trucked down to the staging post at the Anatori River.

Three teams that searched overnight have been rotated out for three new teams who will being doing more detailed searches into the hills today.

A search dog that was assisting in the search last night has been swapped out due to continuously working on the rough terrain.

Late last night two search teams were winched into the headwaters, in the vicinity of The Fosters Lookout, and will be searching downhill towards the river today.

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

Police continue to make use of the USAR drone that will also be searching the wider area for heat and light.

Search management have been making extensive enquiries to corroborate differing reports of the expected return date of the pair.

Police are still yet to confirm if either the footprints or a historic campsite located near the Webb River yesterday belong to the pair.

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

Anyone with information should contact Police on 105 and quote event number P042228949.

© Scoop Media