WARNING: SOME PEOPLE MIGHT FIND THIS UPSETTING

Footage of an attack on an Afghan village involving elite New Zealand forces has been made public for the first time and shows helicopters opening fire after seeing weapons.

Hit & Run co-author Nicky Hager has released previously secret footage and reports obtained from the US military about Operation Burnham through a court case in Washington DC.

The announcement comes amid a Government probe into allegations in Hager and war reporter Jon Stephenson's book that elite New Zealand SAS soldiers took part in a raid that killed six civilians and wounded 15 others in 2010.

The material released on Friday also included a 74-page report and photos from a US military investigation into civilian casualties on the ground that has not previously made publicly.

Playing two clips of video taken from the guns of US helicopters, one showing people on the ground being shot at by exploding rounds, Hager told reporters on Friday he believed the people in the footage may have just been villagers, not insurgents.

The first video shows two people in a group - previously described by the military as armed insurgents - carrying weapons - including a rocket propelled grenade.

"The explanation for the initially highly suspicious video is that it shows some villagers helping to hide Abdul Ghafar's two weapons in case the house is searched and the weapons get the family in trouble," he said.

But he accepted that it appeared the military had made a logical decision, given the suspicious situation.

The most significant piece of video, Hager said, was a second clip showing a group of suspected insurgents being shot at on a hillside before one man - not visibly armed - climbs down towards a village.

"Now he's walked right into the middle of a village where there are women and children running around ... and the craziest thing of all in the raid is when they fired on him," Hager said.

"These militaries will have an absolutely unbendable rule that they were not allowed to do any firing while civilians [are] around ... They never should have pulled the trigger."

Some of the footage has been released to the media although Hager has held back part of the shooting footage showed to reporters on grounds of sensitivity.

The New Zealand Defence Force has previously confirmed the US military held three hours of continuous helicopter footage of the raid, although Attorney-General David Parker said it did not conclusively answer issues raised in Hit & Run.

Hager said the NZDF's secrecy about releasing the material needed to be explained.

"They were being grossly secretive and obstructive," he said.

"The US military released it without fuss."

Hager and lawyer Deborah Manning earlier this year filed a case under the US Freedom of Information Act requesting information about Operation Burnham.

In a statement, the NZDF said it was pleased the footage confirmed there had been insurgents in the village.

"It should be noted that the material being released today is only a very small part of the material that the NZDF has passed to the inquiry," a spokesperson said.

"The NZDF has provided thousands of items to the inquiry, including up to eight hours of near continuous Intelligence, Surveillance and Reconnaissance footage from Operation Burnham, and all the Apache camera footage it has in its possession."

They said the NZDF has asked the US military to release the helicopter footage "but the request was formally declined on the basis that the material remained classified at that time".

The material has now been declassified by the US military.

"Further US Government footage relevant to Operation Burnham remains unavailable for public release. This footage remains classified because wider dissemination may provide our adversaries with information about our surveillance and reconnaissance capabilities," the US Embassy said in a statement.

The Government, in April last year, launched an inquiry into Operation Burnham, aiming to establish the facts in connection with the allegations, examine the treatment by the NZDF of the reports of civilian casualties and look at the conduct of NZDF.

The Inquiry said it would be releasing its findings on Monday and that it had delayed the release to allow Hager to read the report.

The SAS operation in Taliban-held Afghanistan was to target insurgent leaders behind attacks on New Zealand and other coalition troops.

Hit & Run claimed the SAS had carried out a "revenge" raid which left six civilians dead, including a 3-year-old girl named Fatima, the authors said.

The NZDF has rejected the claims, saying nine insurgents were killed.

The assault came after the 2010 death of New Zealand Lieutenant Tim O'Donnell in a province neighbouring the Bamiyan district where New Zealand's Provincial Reconstruction Team was based.

Last week, Stephenson backtracked on claims in Hit & Run that no insurgents had been present during the attack, contradicting accounts of villagers in the book, after speaking to Taliban fighters who admitted to being in the area.

"The villagers may have a reason, they may genuinely have not known they were there, they may have been scared to have acknowledged their presence for fear of retaliation, or they may have been Taliban sympathisers," he said.