Australia’s Special Forces are facing more disturbing war crimes allegations surrounding their involvement in the Afghanistan war.

A U.S. Marine helicopter crew chief has detailed an incident wherein members of the Second Commando Regiment — an Australian Special Forces unit — appeared to have killed an Afghan prisoner. The Marine says Australian special forces shot and killed a bound Afghan prisoner after being told he would not fit on the U.S. aircraft coming to pick them up:

“And the pilot said, ‘That’s too many people, we can’t carry that many passengers.’ And you just heard this silence, and then we heard a pop. And then they said, ‘OK, we have six prisoners.”

“So it was pretty apparent to everybody involved in that mission that they had just killed a prisoner that we had just watched them catch and hogtie,” he added.