Burgess said somerepatriated Australians may need to be monitored after their return.

“That’s ok because I’ll back my organisation any day,” he said.

Burgess said ASIO had conducted risk assessments involving face-to-face interviews with the entire cohort ofAustralians in the camps.

Burgess announced in ASIO’s annual report that foreign interference had overtaken terrorism as the agency’s principal national security concern.

Burgess stressed the threat of terrorism had not extinguished and that “possible” does not equate to “negligible”.

“It remains plausible that someone will die at the hands of a terrorist in Australia within the next twelve months,” he said.

“Individuals are still fantasising about killing other Australians,still spouting their hateful ideologies in chat rooms,still honing their capabilities by researching bomb-making and training with weapons.

“Critically,though,there are fewer of these people than there were previously,and fewer of them are likely to conduct an actual attack in Australia.”

The most important factor in reducing the threat level was the reduction in risk posed by religiously motivated violent extremists,he said.

“The offshore networks,capabilities and allure of groups such as ISIL and al-Qaeda have been degraded,with their support in Australia declining accordingly,” he said.

“But I stress:it’s dissipated,not disappeared.”

The most likely terrorist attack in Australia involves a lone actor using a basic,easily obtained weapon such as a knife or vehicle,he said.

Home Affairs Minister Clare O’Neil said the government and security agencies would “remain vigilant”.

“Terrorism doesn’t stand still,and neither will we.”

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