A soldier faced disciplinary action after he set off a Claymore mine in a live firing exercise in Afghanistan, injuring himself and another soldier.
The soldiers suffered shrapnel wounds after one of the pair tried to "improperly dispose" of the mine after it failed to detonate during training to fight insurgents in Bamiyan Province on February 15, 2013.
The incident, which had been kept quiet by the Defence Force, was revealed in a wide-ranging Official Information Act request into the use by the Defence Force of controversial Claymore mines.
According to a briefing note prepared by Crib 21 command, the incident occurred as a Kiwi patrol trained for an operation against enemy insurgents.
A Claymore mine failed to detonate and when a soldier tried to dispose of the device it exploded.
The two men were struck in the wrist and leg by shrapnel.
The soldiers - a corporal medic and a lance corporal - were described as "walking wounded" and taken to Bagram Airbase hospital, 180km east of the Kiwi province.
One soldier returned to New Zealand three days later and the other was able to continue with the Crib 21 deployment, the final rotation of 10 years of Kiwi presence in the area.
The soldier was charged under the Armed Forces Discipline Act, and was fined and banned from taking part in subsequent firing exercises.
Ten New Zealand soldiers were killed in Afghanistan during the 10-year deployment, which ended in April last year.
Herald on Sunday inquiries were sparked by a former Defence Force corporal's claims he had been ordered to illegally modify Claymore mines so they were tripwire-activated.
Doing so would be in breach of international anti-landmine treaties.
He said the order, given by a senior commander, was never carried out.
Chief of Defence Lieutenant General Tim Keating said Kiwi forces had not tried to modify Claymores, and had always used them in accordance with international law.