New counterterrorism units will be established at Australia's international airports as the Abbott government cracks down on home-grown militants joining terrorist groups in Syria and Iraq.
Prime Minister Tony Abbott told the House of Representatives on Wednesday that two new border force units began operating at Sydney and Melbourne airports last week.
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PM announces new counter-terrorism units
Additional border-force officers will be stationed at international airports across the country says the Prime Minister.
"I am advised that these new units have already intercepted at least one person of interest," Mr Abbott told the Parliament.
A further 80 officers will be stationed at other major airports to monitor the movements of people on Australia's national security watch lists.
Biometric screening will also be introduced soon at Australia's international airports.
The move came as police on Wednesday were questioning a terror suspect who had boarded a plane about to leave Melbourne headed for Lebanon.
According to ABC TV news, the man was taken off the plane preparing to depart Melbourne Airport after a passport check revealed he was on a terrorism watchlist.
The ABC reported that spy agencies believe the man has links with Syria and feared he was ultimately headed there. He was being detained on Wednesday night.
Mr Abbott said at least 60 Australians were known to have gone to fight with terrorist groups in Syria and northern Iraq, including the Islamic State movement.
"And, regrettably, Madam Speaker, about 100 Australians are known to have been supporting or facilitating these terrorist groups," he said.
ASIO boss David Irvine, in a speech to the National Press Club on Wednesday, said young Australians were being recruited by terrorist groups in ways that put them on a path to carrying out suicide bombings in Iraq and Syria.
Mr Irvine also said the nation's counterterrorism agencies would look very closely at whether any Australian military action in Iraq or Syria would create a backlash at home and raise the threat level.
Mr Irvine, in a valedictory speech ahead of his retirement in several weeks, also reiterated his defence of planned new counterterrorism laws, saying they were needed to keep the nation safe, would always be subject to oversight and would operate under the rule of law.
On the prospect of possible military action against the brutal Islamic State organisation in Iraq and possibly Syria, Mr Irvine said it may not immediately raise the threat level at home but would be carefully monitored by ASIO.
"There may be some people within Australia who object strenuously, were the Australian government to the take any decision ... to become more involved beyond humanitarian activities in the Syria-Iraq conflict," he said.
"I don't know that it would necessarily raise the threat level, but you could bet your bottom dollar that we'd be looking closely at it."
In his prepared speech, the spy boss said that Australian supporters were "recruiting new fighters to go overseas and indeed grooming potential suicide candidates as well as providing funding and equipment".
Asked to expand on this, he said: "The process of recruitment, which I also think is grooming, is occurring here ... Not necessarily, 'Hey mate come on, we want you to be a suicide bomber,' but a gradual process that reaches its crescendo when the people arrive or are in Syria and Iraq for some time."
ASIO believes that at least two young Australians have already carried out suicide bombings in the region.
Mr Irvine also effectively defended media publication of graphic images of atrocities carried out by the Islamic State, saying that "that's reality" and "it has brought home to us an understanding of the nature of what we are dealing with that many people may not have had before".
The government recently announced an extra $630 million for Australia's security services to tackle the threat of home-grown terrorism.
Mr Abbott on Wednesday stressed that it was terrorism, and not any particular community, that was being targeted.
"I do want to assure the House that this government will do, I'm sure this Parliament will do, everything that is reasonably necessary to keep our country safe," he said.