Troops killed killed four suspected insurgents April 28 in Zabul province, including one man whose hands were chopped off, the Sydney Morning Herald reported Friday.
The troops allegedly took the dead man's hands back to the Australian base at Tarin Kowt, the newspaper said.
It was not known how many troops were being investigated.
Gen. David Hurley confirmed the military was investigating an "incident of potential misconduct" but declined to provide details. In May, he confirmed the military was investigating the killing of four suspected insurgents.
"During the course of clearing the targeted area, the force element positively identified several armed insurgents moving to gain a tactical advantage and due to the threat posed, the combined [Afghan National Security Forces] and [Special Operations Task Group] force element engaged and killed four insurgents," he said.
Hurley said the military takes reports of potential misconduct by Australian personnel "very seriously."
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