( CNN ) -- Thirty armed militants were killed on Thursday during a fight with troops in southern Afghanistan , the U.S. military said . Afghan National Army ( ANA ) soldiers listen to a speach in Nadi Ali district , Helmand province , on February 5 , 2009 . The incident occurred in the Gereshk district of Helmand province , and the militants were killed by Afghan soldiers advised by coalition troops , the U.S. military said in a statement . Afghan soldiers had been conducting `` combat reconnaissance in an area of known militant presence , '' the statement said , when militants fired at the troops with small-arms and rocket-propelled grenades and a firefight eventually broke out . The troops made sure non-combatants were not in the area when they fired at the militants , the military statement said . One Afghan soldier received minor injuries in the incident . `` This engagement was yet another blow to the militants , who are quickly losing their ability to operate in Helmand province , '' a coalition official said in the statement . `` The Afghan National Army is working to rid Afghanistan of extremists who are only trying to destabilize the country and sabotage Afghan freedom . '' Meanwhile , an Australian soldier has been killed by an improvised explosive device Thursday during operations in southern Afghanistan , Australia 's Defense Ministry said . He is the second Australian to be killed in Afghanistan this week . Ten Australian troops have died in the Afghan conflict . Defense Force Chief Angus Houston said the `` soldier was trying to clear the route of an Australian patrol when the explosion happened . '' He was trying to defuse the explosive when `` there was an explosion and he was killed , '' Houston said . Houston said the soldier was an expert in countering roadside bombs . `` He lost his life trying to make the environment safe for his mates . At this point in time we do not know what caused the explosion , '' said Houston , who did not say where in the south the incident occurred . On Monday , Australian Cpl . Mathew Hopkins was killed in a firefight in Afghanistan . He had been part of a joint patrol near Kakarak , north of Tarin Kowt in Uruzgan province .
Militants killed during a fight with troops in Helmand province district of Afghanistan . Australian soldiers had been conducting combat reconnaissance . Militants fired at the troops with small-arms and rocket-propelled grenades . Afghan soldier killed by an improvised explosive device in southern Gereshk .