THE prosthetic leg of a prisoner allegedly killed by Australian elite soldiers in Afghanistan was used as a drinking vessel at SAS headquarters in Perth, according to a new report.

Fairfax Media’s investigation — which has been corroborated by special forces insiders — found that during the 2009 incident one SAS soldier, who cannot be named for legal reasons, pushed a bound prisoner off a small cliff, severely injuring his face in the fall during a raid in the remote village of Darwan.

As the prisoner laid on the ground, the elite soldier was allegedly part of a decision to “get him out of his misery” by machinegunning him. The prisoner’s prosthetic leg was then kept and used as a drinking vessel at the special elite forces’ HQ, according to Fairfax Media’s investigation.

The soldier has previously denied that he ever acted inappropriately and said he knew nothing about the incident, any detainee being kicked off a cliff or even the raid itself.

The alleged incident is one of several allegedly involving a rogue Special Air Service Regiment team which has been uncovered by a Fairfax Media and backed by elite defence force personnel.

On the same mission in 2009, a trooper on his first deployment to Afghanistan was allegedly pressured to execute an elderly, unarmed detainee by fellow higher-ranking soldiers as part of a “blooding” ritual, according to defence insiders who were witnesses at the scene.

These behaviours, along with new allegations that have surfaced through an internal inquiry — have raised questions about the chain of command within the SAS and the behaviour of Australia’s most highly trained forces.

In a separate incident a young boy was killed during a suspected helicopter assault on a compound in Uruzgan, believed to have occurred between 2012 and 2013.

Following the allegations, the army confirmed a review had been under way since 2015 looking at a range of cultural and governance reforms in the special forces.

Former security boss David Irvine is conducting the independent assessment of efforts made to reform parts of Australia’s special forces.

Defence Minister Marise Payne on Friday confirmed the inquiry started in May 2016 at the request of the chief of the army and the direction of the chief of the defence force.

Australian War Memorial director Brendan Nelson said if any laws of armed conflict were breached it should be known, but he stressed the need for people to reserve their judgment until the facts were clear.

“I think it’s better that we not pass judgment on any of these men, and the women by the way, who are part of special operations until we know precisely what the facts are,” he told the ABC on Sunday.

The Australianreported that two brothers had been working as shepherds near the compound where they were attacked by troops. It is understood the reason for the attack related to the long sticks they carried to manage their flock of sheep.

It was reported that the soldiers thought one of the sticks was a radio antenna and that the boys were acting as spotters or lookouts for the Taliban and had to be killed to ensure the element of surprise in the raid — it resulted in one boy getting wounded and the other shot dead.

The Australian has confirmed investigators from the Inspector General of the Australian Defence Force (IGADF) have reached out to Afghanistan human rights workers seeking details of any reports filed to Afghanistan authorities about the case.

Another incident the IGADF is investigating involves the killing of a father and son during a raid. Villagers alleged the father was sleeping with his young son in bed when he was shot. The bullets also killed the son.

Soldiers involved in the raid had claimed the father had pointed a pistol at them and they did not realise there was a child in bed as well, according to The Australian.

In a statement, the Australian Defence Force said an ongoing inquiry by its Inspector-General, assisted by NSW Supreme Court judge Paul Brereton, would make “recommendations” about how to deal with any substantiated allegations of war crimes.

The IGADF investigation is expected to be concluded by the end of the year.