The Education Council has confirmed that it is investigating allegations which are believed to involve a relationship between a 19-year-old woman and her former teacher.
The young woman's mother has told the Stuff news service that her daughter has left the country with her former teacher, who was described as a man "understood to be in his 50s".
The man had taught the young woman "for two years, before she reached high school", Stuff reported.
The Education Council said: "We can confirm the Education Council is investigating a lower North Island teacher, and the investigation has been ongoing since July 2017."
Although the alleged relationship is legal because the young woman is over the age of consent of 16, the Teachers Disciplinary Tribunal has previously ruled that relationships between teachers and former students can still be inappropriate.