SYDNEY - Australian warplanes will cease their air strike campaign in Iraq and Syria, it was announced Friday, with the country's six hornet jets heading home after a three-year mission. The decision follows the Islamic State militant group losing its two main hubs, Mosul in Iraq and Raqa in Syria. It is now only clinging to the dregs of a "caliphate" that spanned territory the size of Britain three years ago, with Iraq declaring victory in the war this month. Defence Minister Marise Payne said Canberra had decided to scale back its mission after consultations with coalition allies following more than 2,700 sorties.