Police say details about the movements of two cars between Auckland and Hamilton in a five-day period in June could be vital in finding the killer of Hamilton woman Rae Portman.
Police investigating Ms Portman's death on Thursday evening unexpectedly came across a body they believe is hers at a rural property in Ardmore, on the southern outskirts of Auckland.
Results of a post-mortem examination of the body held on Friday haven't been released but personal items of Ms Portman were found at the Ardmore farmlet and Detective Inspector Mark Gutry says police believed it was Ms Portman.
One man has appeared in court charged with her kidnap and Det Insp Gutry says he won't discount more arrests.
Ms Portman, who was believed to have been involved in the drugs scene, hadn't contacted family or friends since June 20 and hasn't accessed her bank accounts.
But police say sightings of two vehicles - a yellow Holden Commodore ute with the number plate LCKDUP, and a black Mazda Astina - between June 20 and June 25 could lead police to Ms Portman's killer.
"We believe the yellow ute and the black Astina travelled from Papakura to the Hamilton area on the night or early morning of June 20-21.
"We also know the cellphone of Rae Portman travelled to Hamilton and was in the Te Rapa area over the night of June 20-21 and then was back in Auckland on the morning of June 21.
"That's the information we need, as to what took place over that night between Papakura and Hamilton and back, and we certainly need help from the public as to how that all unfolded."
The Astina was later found at a Hamilton wrecking yard, while the yellow Holden is with police in Auckland.
Det Insp Gutry said the residents of the Ardmore property aren't regarded as suspects.
Ms Portman's family have been contacted and Det Insp Gutry hoped the finding of the body gives them some closure.