Australia moved to prosecute alleged war crimes by its special forces deployed in Afghanistan on Thursday, years after harrowing reports emerged of civilians and prisoners being killed.

Australian Prime Minister Scott Morrison - citing allegations of "serious and possibly criminal misconduct" - ­appointed a special ­investigator, a move to forestall any prosecution at the International Criminal Court.

After the September 11, 2001 terror attacks, more than 26,000 Australian uniformed personnel were sent to Afghanistan to fight alongside the US and allied forces against the Taliban, Al Qaeda and other ­Islamist groups. 

Australian combat troops left the country in 2013, but since then a series of often-brutal accounts have emerged about the conduct of Australia's elite special forces units. 

They range from reports of troops killing a six-year-old child in a house raid, to a dead foe's hand being severed, to a prisoner being shot dead to save space in a helicopter.

For years the government had tried to suppress whistleblower reports of the alleged wrongdoing, with police even moving to investigate reporters involved in bringing those accounts to the public.

Meanwhile, the Australian Defense Force's Inspector-­General conducted one of several closed-door probes into what it called "rumors and allegations" of "possible breaches of the Law of Armed Conflict."

The Inspector-General identified more than 50 incidents, most relating to the unlawful killings of "persons who were non-combatants or were no longer combatants" as well as "cruel treatment."

Morrison said a redacted version of the Inspector-General's report would be released within days, "this will be difficult and hard news for Australians."

The appointment of a prosecutor represents a significant escalation in the legal process and could lead to criminal charges against military personnel. The military is revered in Australia and its campaigns - from Gallipoli to Kokoda - have played a crucial role in ­fostering the country's identity, as ­independent of colonial ­power Britain.

"Serving men and women and our defense forces, both past and present, share the expectations and aspirations of the Australian people for our defense forces, and how they engage in their conduct," said Morrison.

"This is going to be very difficult for Australians," he added. "This requires us to deal with honest and brutal truths, where expectations and standards may not have been met."

There had been speculation that Australia's failure to fully investigate the reports could lead to the International Criminal Court stepping in.