The teenage sister of a woman who died on New Year's Eve in the Northland town of Ruakaka, near Whangarei, has been arrested.
The police were called to a Te Kamo Rd house by the ambulance service at about 9.25pm after a report that a 30-year-old woman had been stabbed in a family dispute.
Detective Senior Sergeant Dene Begbie says officers tried to keep the victim alive but she died at the scene.
The woman's 15-year-old sister has been arrested on assault charges and will appear in the Whangarei Youth Court on Saturday.
Mr Begbie says further charges are likely but that will not be decided until after the results of the post-mortem, which was under way on New Year's day. The police are not looking for anyone else.
A scene examination involving ESR scientists is continuing.