The New Zealand Defence Force is investigating an assault allegedly centring around a more senior staff member "ill-treating" a lower ranked naval rating.
The investigation was launched this week after an incident at the Navy Dive School in Devonport.
A Defence Force spokesman said: "We can confirm an investigation into allegations of ill-treating a person of a lower rank and minor assault is being carried out at the Navy Dive School in Devonport."
It is understood the incident happened on Wednesday and was then reported to senior staff.