SYDNEY (AFP) - The Australian military Friday said it was investigating allegations that its troops mistreated suspected insurgents in Afghanistan, shortly after a special forces soldier was killed there.

A senior Afghan National Army commander raised concerns about the treatment of four alleged Taliban fighters at a meeting of international forces and local commanders last weekend, the Australian Defence Force said in a statement.

Australian public radio reported that the claims centred on four alleged insurgents taken into custody after Australian soldier Jason Marks was killed during a battle in southern Uruzgan province on April 27.

The Australian Defence Force (ADF) would not confirm the details or outline the nature of the alleged mistreatment.

"We take all of these claims very seriously and have consistently shown our willingness to be part of investigations into these matters," Australian national commander for the Middle East, Major General Michael Hindmarsh said in a statement.

"Our troops are well-versed in their procedures regarding the safe and humane treatment of detainees and we take our legal obligations in this regard extremely seriously."

Australia has around 1,000 troops in Afghanistan, the largest deployment of any non-NATO country, mostly assisting a Dutch-led reconstruction operation in Uruzgan, a former Taliban stronghold.

Lance Corporal Marks, 27, was killed in a firefight with Taliban fighters that the ADF said was characterised by a heavy exchange of small arms fire and rocket propelled grenades.

Four other Australian troops received non life threatening injuries in the exchange.

Marks, a special forces soldier, was the fifth Australian to die in combat in Afghanistan since 2002 and the fourth in the past seven months.

LIKE IT?  LET OTHERS KNOW