INDONESIA - Indonesian Abdul Rahim Ayub fought alongside militants in Afghanistan in the 1980s before Jemaah Islamiah leader Abu Bakar Bashir named him to lead the clandestine group's cell in Australia.
Now his son, Australian Mohammed Ayub, 26, has been reported fighting alongside Al-Qaeda linked radicals in Syria over the past year, posting his war pictures on Facebook alongside a flag of the hardline group Islamic State of Iraq and Syria.
Ayub is one of three Australians fighting in Syria sharing their stories online, The Australian newspaper reported on Tuesday, as Canberra warned that the conflict in Syria posed new risks of homegrown extremism.
The case of the Ayubs reveals how the children of Afghan veterans steeped in radical ideology now see Syria as a battleground to keep their cause alive and win new recruits.
"These individuals not only potentially breach Australian laws and commit offences offshore, but upon their return to Australia they pose a significant national security risk," Australia's Attorney-General George Brandis told an Interpol meeting on security and Counter-Terrorism in Sydney.
They "can become radicalised and obtain new skills - including the ability to conduct an attack on Australian soil, radicalise others and impart knowledge and skills gained offshore".
Officials estimate about 100 Australians are fighting in Syria, and Mr Brandis said the Syrian conflict presented a "complex set of global security challenges" that extend far beyond the Syrian border.
Recently, Indonesian counter-terror officials said about 50 Indonesians are fighting in Syria, and analysts estimate several hundred European militants have also made their way there.
And in the case of Mohammed Ayub, regional officials and analysts say his involvement in the frontline reflects how old JI networks are being rekindled, with a new generation of militants using social media to recruit and engage fellow radicals.
"JI members and people with JI connections are still those with the best channels to groups abroad," an Indonesian analyst, with access to JI members, told the Straits Times.
"And while they have disengaged from violence at home, it doesn't mean they disengage from violence elsewhere. The Syrian conflict is a rallying point for them."
Mr Mohammed Ayub and his brother Abdullah Ayub were detained by Yemeni authorities in 2006 for alleged arms trafficking, but released without charge.
Their mother, Australian-born convert Rabiah Hutchison, has links to high-ranking members of terrorist groups in Indonesia and also spent time in Afghanistan and Yemen.
Mr Brandis said the Syrian conflict was also stoking tensions between Australia's Sunni, Shia and Alawi Muslim communities, leading to local outbreaks of violence.
He also said there was a "real" threat of an extremist attack on Australian soil.
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