A NZ Special Air Service soldier has confirmed civilians were killed in a 2010 raid carried out by the unit and says the truth is widely known among the elite military group.
The soldier told the Herald the two people found shot dead were killed by NZSAS marksmen who believed they were acting under "Rules of Engagement" governing their actions on the battlefield.
"They have taken out two," he said.
He said the other four people killed died in a barrage of fire from United States aircraft called in by a New Zealander operating as the joint terminal air controller - the person responsible for directing air support.
The soldier said it emerged no combatants were identified on the battlefield.
But he said the lack of an obvious opposing force contradicted the soldiers' expectation based on the United States-sourced intelligence used to frame the Rules of Engagement and the raid itself.
• NZSAS killed civilians in raid, Nicky Hager's new book claims
• A Kiwi soldier dead; a firefight ignites
• David Fisher: Grim assertions - if true - spell serious betrayal of public trust
• Defence chief: Hager's 'revenge raid' book could harm New Zealand's reputation
• English says SAS allegations don't appear to be new
The controversy over the NZSAS and civilian casualties has been sparked by the release of a book, Hit & Run, written by author Nicky Hager and war correspondent Jon Stephenson.
It alleged six civilians were killed and 15 injured in a "revenge" raid after the death of New Zealand soldier Lieutenant Tim O'Donnell on August 4, 2010.
It alleged New Zealand was responsible for the deaths and injuries - including those killed by air support - because NZSAS troops sourced intelligence as to who was responsible for O'Donnell's death, then planned the raid and carried it out, relying on United States' resources at all stages.
Hit & Run stated the raid was unsuccessful and none of those implicated in O'Donnell's death were killed.
The soldier's account of the raid largely supported one of the main contentions in the book, which is that civilians were killed during the August 2010 raid.
The claim remains in direct conflict with the NZ Defence Force's position since 2011 "that the allegations of civilian casualties were unfounded". The position was attributed to an investigation led by the International Security Assistance Force, which has never been made public.
But the soldier's account also conflicted with claims in the book that the NZSAS were motivated by "revenge" over the death of O'Donnell.
He said the NZSAS soldiers would have been "angry" over the death but "revenge" had no part to play in how they did their jobs.
The soldier said: "SAS boys are a different breed. Everything is a lot more calculated."
Rather than "revenge", the Herald was told by the former Governor of the neighbouring province, the raid was to target insurgents who threatened the New Zealand base at Bamyan, about 50km away.
Although not personally involved in the raid, the soldier - who has served in Afghanistan - told the Herald he learned details of the raid as part of his role in the military, which required detailed information on what happened.
The soldier said the raid saw the NZSAS and soldiers from the Afghan Crisis Response Unit use the New Zealand base in Bamyan as a staging post for the raid. The Bamyan base was an important communications conduit for those on the ground in Baghlan province, he said.
After having dinner at the base, the soldiers set off for the Tirgiran Valley with a plan based on US intelligence reports.
The plan saw a marksman and another NZSAS trooper dropped off by Blackhawk helicopter to provide cover for the soldiers who were to be dropped off by the much larger Chinook transports. As with most Chinook movements, Apache helicopters were in support.
The marksmen were dropped into the general area and walked into a position above the villages. Once there, they "came into contact with potential insurgents on the high ground".
"One of our guys killed one of theirs."
The book stated that one of the Chinooks dropped the first contingent of soldiers near the village of Khak Khuday Dad while the other deposited its group near the larger village of Naik.
The Herald source said the soldiers, having taken up position, saw movement in the area.
"It was people moving to cover. When you see a whole bunch of people moving into high ground, into a threatening position, you need eyes on that position."
One of the soldiers acting as a joint terminal air controller (JTAC) - the liaison between the soldiers and air support - was able to see movement that matched intelligence reports of what to expect from an armed opposing force.
"If your intelligence tells you everyone is armed, then you assume everyone moving from that [area] is armed. If they move into [a position of] advantage, then you assume they are moving into firing position."
He said there were people in one of the villages "running around, dodging, all over the place". It fit the profile of what to expect from the armed group, which intelligence reports had said they were facing.
• SAS defence on civilian deaths at odds with Minister, coalition leaders
• The hardest hitting responses to Nicky Hager's book
• Former Defence Minister concedes civilian casualty in 2010 SAS raid in Afghanistan
• Doubt grows over denials of civilian deaths in SAS raid in Afghanistan
• Barry Soper: Nicky Hager adept at whipping up media frenzy
• Former Defence Minister Wayne Mapp's SAS comments informed by TV, Bill English says
The JTAC then called fire on to the areas of concern, he said.
In a detail not present in Hit & Run, the soldier said the air support called on was a AC130 Spectre gunship - one of the most fearsome airborne elements available to support infantry.
The Spectre gunship is the same basic airframe as the Royal NZ Air Force Hercules but with armaments, including a 105mm howitzer, which is normally a field artillery piece but in the aircraft's case it is mounted in the side of the aircraft.
The soldier said: "It was the first time since the Vietnam War a 105[mm[ howitzer has been used to support [New Zealand] troops on the ground."
The account expands on details in Hit & Run, which said stated air support came from the Apache helicopter gunships - a match with one of the few details later released by ISAF that said a gunship with faulty sights led to rounds of ammunition hitting buildings in one of the villages.
The soldier said the Apache was "a bit inaccurate". "They can't shoot a big vehicle on the side of a hill let alone anything at night."
The Herald source said the bombardment was followed by a ground assault that saw NZSAS soldiers going from house-to-house to clear buildings of any combatants.
As part of the normal assault, flash-bang grenades - sometimes called stun grenades - were thrown into the houses before the soldiers entered.
He said it was a flash-bang grenade, which sparked fires. This contrasts with Hit & Run's claim that the fires were deliberately sparked, apparently by soldiers firing bullets into cotton mattresses and curtains.
The soldier said the fire that consumed homes was not - and could not - be caused in such a way.
As the soldiers moved through the village, it became clear there was no opposing force.
"The info that the boys had been fed was that everyone was a combatant. They were indeed civilians."
The soldier also detailed the serious injuries suffered by one of the NZSAS when a wall, weakened by the aerial barrage, collapsed. The trooper broke numerous bones, including both legs, shoulder blade and jaw, he said.
The soldier, who was one of the leaders, was later awarded the NZ Gallantry Medal for continuing to lead his soldiers despite his serious injuries, he said. He had since recovered and returned to active service.
The soldier said it was not the only situation in which there had been civilian casualties from a NZSAS operation and which the soldiers blamed on faulty US-sourced intelligence.
The soldier said a number of those involved in the raid had received medals for their roles, which sat uncomfortably when the civilian casualties emerged.
Among those who received a medal was the JTAC soldier who called in the airstrike, he said.
In the months that followed the raid the discovery civilians had been killed troubled the NZSAS greatly, he said.
"Once the civilian casualties came out of it, obviously you started questioning each other."
He said it became a topic of conversation among the troops with soldiers questioning each other's actions and decision-making.
Within the group, there was a hard-edged banter about the medals some soldiers received for their actions during the raid. The JTAC had received the New Zealand Distinguished Service Decoration and was told by others - not entirely seriously - "you've got to give that back".
He said it was discomfort over the civilian deaths that drove the NZSAS troopers to question their actions.
He said he did not know why the civilians casualties had not been made public. "Whatever decision was made to suppress that was made higher."