Police in Northland say they have found a number of items of interest as they investigate an attack on three Chinese tourists.
Police have been examining the scene and the vehicle the tourists were driving. A number of items of interest have been sent away for scientific testing.
The tourists were attacked on Friday after stopping to help two men who flagged them down, claiming to be lost.
They were robbed at knifepoint at the side of a gravel road running through Te Paki, leading to 90 Mile Beach.
Detective Sergeant Trevor Beatson says there has been a sighting of the car thought to be involved.
He says there is a lot of uneasiness in the area and what is needed now is information from the public to make the men accountable.
The tourists have indicated they want to see their attackers brought to justice, before returning to China.
Far North Mayor Wayne Brown says the incident is already being reported in overseas media and will have international implications for New Zealand tourism.