Three Australian soldiers have been killed and seven injured in a helicopter crash in the rugged north of Kandahar Province in Afghanistan.

It is believed at this point that the helicopter was not shot down by enemy fire but it is unknown what caused the crash, Defence Force Air Chief Marshal Angus Houston.

"This was not the result of enemy action," Air Chief Marshal Houston said.

Other Coalition helicopters were able to land nearby the crash site and recover the bodies and wounded soldiers.

Of the seven wounded soldiers, two are in a serious condition and have been airlifted to a US Air Force base at Bagram.