CANBERRA, Australia: The alleged Sydney ringleader of a criminal network that sends Australians to fight in Syria has been arrested, police said Tuesday. Officials estimate about 100 Australian residents and citizens traveled to Syria to fight in contravention of Australian law, some taking up arms with terrorist-linked militias. Two Sydney men became the first suspects to be arrested by a four-month-old joint federal and state police counterterrorism investigation into Australian citizens attempting to travel to Syria to fight, Australian Federal Police Deputy Commissioner Peter Drennan said. The 39-year-old suspected ringleader and a 23-year-old suspected recruit are expected to be charged under the Crimes (Foreign Incursions and Recruitment) Act. The act outlaws Australian residents or citizens traveling overseas to fight or recruiting others. It carries a maximum 10-year prison sentence. New South Wales state Deputy Police Commissioner Catherine Burn said the network had already sent six Australians to Syria to fight.