A 24-year-old man and a 17-year-old teenager have been charged with foreign incursion offences after they were arrested by NSW Joint Counter Terrorism officers in Sydney's southwest on Thursday morning.
Counter-terror officers arrested 24-year-old Mehmet Biber at a traffic stop in Birrong after executing search warrants on several homes across Sydney's southwest as part of an ongoing investigation.
Police will allege Biber was one of seven Sydney men who travelled to Syria to fight with terrorist group al-Nusra against Bashar al-Assad's regime under the orders of convicted ISIS recruiter Hamdi Alqudsi in 2013.
“What we would say generally is that if people have travelled to either Syria or Iraq or some other hostile place where there are hostile activities under way, we would say that they would potentially become ... more extreme and have greater capability to potentially do some attack,” NSW Police Deputy Commissioner Catherine Burn said at a press conference on Thursday.
The teenager is accused of trying to travel to Syria to fight with ISIS in January last year.
Burn said the pair were "linked by association" and that they both had a "common motive" to "go to Syria to engage in hostile activities".
"We have to work with everybody so that we can really eliminate what we are seeing happening with some of our young people who might be susceptible or vulnerable to radicalisation for violent extremism," Burn told reporters.
Prime minister Malcolm Turnbull was asked whether the two-and-a-half-year delay in arresting Biber since he allegedly travelled to Syria was "unusual".
"It always takes time to turn intelligence into evidence," Turnbull responded.