A range safety officer spreads CS gas during a live fire range August 18, 2016, to simulate a chemical attack at Bradshaw Field Training Area, Northern Territory, Australia. The range was the final training evolution of Exercise Koolendong 16, a trilateral exercise between the U.S. Marine Corps, Australian Defence Force and French Armed Forces New Caledonia. Marines held a defensive position while engaging targets and working through the CS gas. - A range safety officer spreads CS gas during a live fire range August 18, 2016, to simulate a chemical attack at Bradshaw Field Training Area, Northern Territory, Australia. The range was the final training evolution of Exercise Koolendong 16, a trilateral exercise between the U.S. Marine Corps, Australian Defence Force and French Armed Forces New Caledonia. Marines held a defensive position while engaging targets and working through the CS gas.