The New Zealand Defence Force (NZDF) says it is "confident" the SAS didn't commit any war crimes during a raid in Afghanistan.
Investigative journalists Nicky Hager and Jon Stephenson have alleged 21 civilians, including a three-year-old girl, were killed or injured during a revenge raid following the death of a Kiwi soldier.
Further, they allege that, supported by US and Afghan forces, the SAS burned and blew up about a dozen houses and failed to help the wounded.
"There are grounds to suspect that there have been war crimes," Mr Hager says, calling for a royal commission of inquiry.
It's an allegation the NZDF has repeatedly denied.
"The New Zealand Defence Force stands by the statement it made dated 20 April 2011," they say.
"As the 2011 statement says, following the operation, allegations of civilian casualties were made. These were investigated by a joint Afghan Ministry of Defence, Ministry of the Interior and International Security Assistance Force (ISAF) assessment team, in accordance with ISAF procedures.
"The investigation concluded that the allegations of civilian casualties were unfounded.
"The NZDF does not undertake investigations or inquiries into the actions of forces from other nations. That was the role of the joint Afghan-ISAF investigation.
"The NZDF is confident that New Zealand personnel conducted themselves in accordance with the applicable rules of engagement."
The acting Minister of Defence Christopher Finlayson is unavailable to comment on the allegations.
"The matter was investigated at the time and I am advised by the New Zealand Defence Force they stand by what they said at the time," a spokesperson for Mr Finlayson says.
The book's allegations
Mr Hager's and Mr Stephenson's book, Hit and Run, released on Tuesday evening, describes the events and alleges that Former Prime Minister John Key signed off on the raid.
Labour leader Andrew Little has reacted to the newly released book, saying Mr Hager and Mr Stephenson have raised "serious allegations" about the conduct of the SAS in Afghanistan.
"The Defence Force’s reputation is at stake so the Government must provide a comprehensive response. This cannot be swept under the carpet," Mr Little told Fairfax.
Hit and Run describes a series of operations including "an SAS attack on two isolated villages in Afghanistan's Baghlan province where they mistakenly believed they would find the insurgents who'd attacked a New Zealand patrol 19 days earlier in neighbouring Bamiyan. SAS officers commanded and led the attack, supported by US and Afghan forces."
"The insurgent group wasn't there. Instead, at least 21 civilians were killed and injured, many of them women and children and the SAS and US forces burned and blew up about a dozen houses."
"The SAS also failed to help the wounded. The defence force and government then tried to keep the whole thing secret. They have never admitted nor taken responsibility for what they did."
A second raid is discussed which occurred about ten days later, "the SAS destroyed more property. When they eventually caught one of the targeted insurgents in Kabul he was beaten before being handed to the Afghan secret police and tortured."
The book says Former Prime Minister John Key approved the operation.
The book's authors, alongside former chief human rights commissioner Margaret Bedggood, are calling for "a full, principled and independent inquiry into the actions described in this book, which, if confirmed, would seriously breach international law."
"Whether or not the public agreed with New Zealand sending troops to the US-led war in Afghanistan, there is no doubt that what the SAS did was wrong and betrayed the defence force's core values of courage, commitment and integrity," Mr Hager said in a press release.
Mr Hager and Mr Stephenson launched the book at Unity Books in Wellington on Tuesday evening.
Mr Hager's previous books have had a big impact on election campaigns, most notably Dirty Politics, released in 2014, which alleged dirty tricks by the National Party.
His other books are Secret Power, Secrets and Lies, Seeds of Distrust, The Hollow Men, and Other People's Wars.
Mr Hager is currently New Zealand's only listed member in network the International Consortium of Investigative Journalists (ICIJ).
Mr Stephenson is an investigative reporter known for reporting foreign conflict and trauma. His previous work includes an investigation titled Eyes Wide Shut - The Government's Guilty Secrets in Afghanistan, published in Metro about New Zealand's role in handling prisoners in Afghanistan in 2002.