There have been a number of homeland deaths among defence force personnel in recent years.
The Defence Force has confirmed a member of the Special Operations Force died during maritime counter-terrorism training this morning.
The Defence Force website describes the Special Operations Forces as a highly capable force, set up to pre-empt threats to New Zealand.
It is tasked with providing military special operations support to domestic, regional, and global security situations.
Recent Homeland deaths
The Defence Force pleaded guilty in 2013 to a charge of failing to take all practicable steps to ensure the safety of Private Michael Ross during a training exercise.
The 29-year-old drowned when he fell from an inflatable boat into a small lake within the Army's Waiouru Military Camp, in September 2012.
An inquiry found a series of failings contributed to his death.
In 2010, an Air Force helicopter crash on Anzac Day killed three servicemen at Pukerua Bay, north of Wellington.
The Defence Force pleaded guilty to failing to provide a safe workplace in a private prosecution taken by the sole survivor.
A court of inquiry into that tragedy found there was a culture of rule-breaking in the Air Force.
The chief of the Defence Force apologised to the family of an Air Force sergeant who died while on duty in 2009.
Sergeant Andrew Forster, 46, was killed instantly when an artillery shell exploded at Waiouru Military Camp in 2009.
A Court of Inquiry found procedures for marking unexploded ammunition were not strictly followed.
Sailor Byron Solomon died while on a Navy exercise in 2007 during a training exercise off Cape Reinga.
A coroner ruled that Able Seaman Byron Solomon's drowning in the training exercise was unnecessary and preventable.
Between 2004 and 2006 there were six deaths across three separate Unimog accidents during routine Defence Force exercises in New Zealand.