organization, and forced them to retreat from the al-Dolab area, which lies 10 kilometers from Ain al-Assad base." Sheikh Mahmud Nimrawi, a prominent tribal leader in the region, added that "U.S. forces intervened because of ISIL started to come near the base, which they are stationed in so out of self-defense," he responded, welcoming the U.S. intervention, and saying "which I hope will not be the last." This was said to be the first encounter between the United States and the Islamic State, in four years. However, this claim has been stated to be "false" by The Pentagon. On 5 January 2015, The Pentagon acknowledged that ISIL had been ineffectively mortaring the base. In late February 2015, another 1,300 US soldiers were deployed to Iraq, increasing the number of US ground troops in Iraq to 4,400. On 9 March 2020, the Pentagon released a statement claiming that two American Marines were killed on 8 March 2020 during an anti-ISIS operation in a mountainous area of north central Iraq. Col. Myles B. Caggins III, a spokesman for the OIR coalition, later identified the Marines as Gunnery Sgt. Diego D. Pongo, 34, of Simi Valley, California, and Capt. Moises A. Navas, 34, of Germantown, Maryland, who were also MARSOC Raiders, and that they died during an operation which also claimed the lives of four ISIS fighters during an American-led operation which involved clearing an ISIS cave complex in the Makhmur Mountains, south of Erbil. The coalition officially concluded its combat mission in Iraq on 9 December 2021, but U.S. troops remained in Iraq to advise, train, and assist Iraqi security forces against the ongoing ISIL insurgency, including providing air support and military aid. Australian airstrikes On 3 October 2014, Prime Minister Tony Abbott and the Australian Cabinet approved for RAAF Boeing F/A-18F Super Hornet fighter bombers to begin airstrikes against Islamic State militants. Abbott said "It is in our national interest that we do so, it is in the interests of civilisation that we do so. It is in everyone's best interests that the murderous rage of the ISIL death cult be checked and rolled back and that's what we're determined to do." On 6 October, Air Chief Marshal Mark Binskin announced two Super Hornets had conducted armed combat missions over Iraq although no armaments were expended. An Australian Air task Group KC-30A and an E-7A Wedgetail Airborne Early Warning and Control