Police in Hawera yesterday charged a 24-year-old woman with making a false rape complaint.
However, they are continuing to investigate the rape of a 22-year-old woman on Christmas Day in the Taranaki town.
A team of around 11 detectives was already working on that case when a second complaint of a very similar nature was made.
As they inquired into the second incident, they said, they became concerned about the authenticity of the allegation.
They interviewed the woman yesterday and were satisfied there was no second attack, said Detective Senior Sergeant Keith Borrell.
The 24-year-old woman will appear in the Hawera District Court on Monday charged with making a false complaint.
"It is important that all rape allegations are treated as genuine until evidence proves otherwise.
"On this occasion we are now satisfied that we are dealing with one isolated offence and although one offence is still a serious matter, we hope that the community is in some way reassured that we are not dealing with a serial offender," Mr Borrell said. "I also hope this does not deter genuine victims of sexual assault from coming forward."
In the Christmas Day incident, a woman was attacked and sexually assaulted by a group of men in a carpark opposite St Joseph's Church between midnight and 1.30am.
The woman was walking alone along High St when she was grabbed.