Former Prime Minister of Australia Kevin Rudd says he's "disgusted" that Australian soldiers serving in Afghanistan could have committed cold-blooded murder.
Rudd was Australia's leader during part of the military engagement in Afghanistan, which is the subject of a scathing investigation into the behaviour of special forces personnel.
A four-year investigation by Inspector-General of the Australian Defence Force, Paul Brereton, found credible evidence of 23 incidents in which a total of 39 Afghan nationals were unlawfully killed.
The inquiry has recommended the chief of defence refer 36 matters to the Australian Federal Police for criminal investigation, involving 19 individuals.
Rudd compared the behaviour to that of the Abu Ghraib torture and prison abuse scandal.
"It beggars belief that following the atrocities witnessed during the Iraq war at Abu Ghraib that such crimes could be repeated, and worse, by Australian forces in Afghanistan," he said in a statement.
He joined with Prime Minister Scott Morrison in offering an apology to the government and people of Afghanistan, and backed the need for compensation and justice to be served.
"These accounts represent flagrant violations of our solemn legal obligations ... as well as a betrayal of the moral and ethical code that Australians expect their military to advance and defend," Rudd said.
The families of those killed, mostly between 2009 and 2013, will be compensated without waiting for any criminal prosecutions.
Justice Brereton found credible evidence some soldiers carried weapons and military equipment which they would plant to make it appear the person killed was a legitimate target.
As well, there was evidence junior soldiers were required by their patrol commanders to shoot a prisoner in a practice known as "blooding" to notch up their first kill.
Chief of the Defence Force, Angus Campbell, blamed a "self-centred warrior culture", also offering an unreserved apology to his military counterpart in Afghanistan and that country's people.
"The killing, the unlawful killing, of civilians and prisoners is never acceptable. It is my duty and that of my fellow chiefs to set things right."
General Campbell accepted all of the 465-page report's recommendations.
Units and individuals are expected to be stripped of medals, the second squadron Special Air Service will be disbanded and disciplinary action will be imposed where tougher sanctions are not justified.
Defence Personnel Minister Darren Chester said it was important the actions of a few did not stain the reputations of the more than 39,000 personnel who were deployed to Afghanistan.
"For the overwhelming majority their service was in keeping with the values we expect as a nation, and the high standards they demand of each other," he said.
Media executive Kerry Stokes is understood to have set up a special fund to back the legal and other costs of current and former soldiers named in the report.