Police have urged the public to contact them if they know about a crime, rather than posting it on Facebook.
Police in Kerikeri made the plea after investigating reports on social media of a sexual assault at the Rainbow Falls walking track.
Posts about the alleged assault has been circulating on Facebook for several weeks.
Inspector Al Symonds said no sexual assaults in the Rainbow Falls area had been reported to police. What had been reported were incidents of "boorish behaviour" towards women walking or running on the track.
Police were planning to speak to a woman in Auckland this week about one such incident. Officers had tried to trace the rape claim back to its source to see if it was genuine. They had so far traced it through a chain of nine people but were no closer to verifying it.
Inspector Symonds urged anyone who thought a crime might have taken place to contact police rather than posting on social media.
"If you don't know something is a fact, please don't tell Facebook. Tell us," he said.
Anyone who felt concerned or threatened, including by behaviour on a walking track, should call police immediately. Police would rather turn up and find an innocent explanation than find out too late about a serious incident, he said.
Despite the apparent lack of substance behind the rape rumour, police would boost their presence in the Rainbow Falls area.
Mr Symonds said there did seem to be a real issue with the behaviour of some men, which he described as "boorish, rude and ungentlemanly".
He called on Northland men to consider the way they treated women, and how they would feel if was their wife, mother or daughter who was subjected to rude comments.
Some years ago Kerikeri was similarly consumed with rumours of a rape on the Domain at a park. Again, no complaint was laid and no evidence was found.