Aussie security agency attempts to ease concerns over fighters from Syria and Iraq

Australia's chief national security agency, the Australian Security Intelligence Organization (ASIO), has moved to ease concerns surrounding fighters returning from Syria and Iraq to Australia, saying the "vast majority" did so before the Islamic State (IS) groups existed.

There are approximately 30 people currently living in Australia who have fought within Syria and Iraq. But ASIO's Director General, Duncan Lewis, said most of them returned prior to the foundation of the IS militant groups.

"Some of them fall into the category of those who were fighting in the Syrian civil war on both sides," Lewis said.

His comments came as Prime Minister Tony Abbott launched Australia's new counter-terrorism strategy, which would enable the government to revoke or suspend the citizenships of people involved in terrorist activities.

But Lewis said that number might be few, with ASIO not strictly monitoring those who have returned from Syria and Iraq to Australian shores.

"We do not have a watchlist, as such," he said. "We manage ... the threat that is presented and the prioritizing of that threat and then the attention that is given to that particular threat."

Approximately 90 Australians have travelled to Syria and Iraq to join violent extremist groups, with around one-third of those people having already returned.

Meanwhile, it has been reported that a high number of Australian women have also travelled to Syria and Iraq to become so-called "jihadi bribes," with several of those women subsequently becoming slaves of the IS militant groups after their partners were killed in battle.

"There are 30 to 40 women that are involved in this cohort that we know of, some of whom have been stopped, some of whom have been successful in getting offshore ... It's a relatively recent phenomenon," Lewis said. Endi