SYDNEY (Reuters) - The Australian police on Wednesday arrested two men suspected of helping Australian citizens fight alongside militants in Syria on terrorism-related charges, officials said, after the intelligence chief warned of mounting threats.
The two, aged 21 and 31, were arrested following a 12-month investigation that agents said revealed their support for an Al-Qaeda-backed militant group the Nusra Front, which seized 45 United Nations peacekeepers in the Golan Heights two weeks ago.
At least 180 federal and state police raided nine properties during the operation in and around suburban Brisbane, which is set to host the Group of 20 summit in November, the police said. "I would like to stress there is no information or intelligence available to police or security agencies at this time to indicate that these males were involved in terrorism attack planning in Australia," federal police Assistant Commissioner Neil Gaughan told reporters.
Australia has raised the alarm about the number of its citizens believed to be fighting overseas, including a suicide bomber who killed three people in Baghdad in July and two men shown in images on social media holding the severed heads of Syrian soldiers.
On Tuesday, the head of Australia's national security agency said he was "very seriously" considering raising the country's terrorism alert level to "high" over Australians' involvement in militant groups and the spiralling conflicts in Iraq and Syria.
Mr David Irvine, the outgoing head of the Australian Security Intelligence Organisation, said the number of Australians returning from fighting with the Islamic State of Iraq and Syria (ISIS) and other radical groups posed a growing risk.
Australia has been at the "medium" alert level since a four-tier system was introduced in 2003. A "high" alert level is used when officials believe an attack is likely. "I would say that, at the moment, it is at a very elevated level of medium and I'm certainly contemplating very seriously the notion of lifting it higher," Mr Irvine told the Australian Broadcasting Corp.
The United Nations Security Council is planning to demand countries "prevent and suppress" the recruitment and travel of foreign fighters to join extremist militant groups like ISIS by ensuring it is considered a serious criminal offence under domestic laws.
The United States circulated a draft resolution late on Monday, obtained by Reuters, to the 15-member Security Council and hopes it can be unanimously adopted at a meeting chaired by US President Barack Obama on Sept 24.
Last month, Australia unveiled counter-terrorism measures aimed at preventing young people from becoming radicalised and going to fight in overseas conflicts. On Wednesday it announced almost A$35 million (S$40.7 million) in new border protection measures intended to blunt terrorist threats.
Mr Irvine said security agencies were aware of at least 20 people who had returned to Australia after fighting in the Middle East, posing a national security risk. Up to 160 people have either been involved in the fighting or actively supporting it, according to Australian officials.
In August, Britain raised its terrorism alert to the second-highest level, with Prime Minister David Cameron saying ISIS posed a serious security threat.