At least 12 Australian women from one city have attempted to join the Takfiri group, ISIL, police said Friday, warning of a trend towards a "romanticized view" of violent Takfiris.

At least 12 Australian women from one city have attempted to join the Takfiri group, ISIL, police said Friday, warning of a trend towards a "romanticized view" of violent Takfiris.

More than 100 Australians have left the country to support ISIL in Syria and Iraq, raising concerns about radicalization and whether they pose a security threat on return, the authorities have said. At least 30 have been killed overseas.

Victoria Police assistant commissioner Tracy Linford said those attracted to ISIL were mostly young, isolated people swayed by slick social media propaganda.

In the case of women, they often had a romantic idea of what life would be like under ISIL control, she said, adding that at least 12 had attempted to join from Melbourne, Victoria's capital city.

"We've got five (women) that we know are over there," Linford said, adding that two more were unaccounted for, four were turned back outside Australia and one was stopped at the airport before leaving.

"But we also suspect that there are probably more than 12," she told reporters.

Linford's comments came just days after a Sydney mother reportedly abandoned her two children and fled to Syria for a new life under ISIL.

"We think that the young women particularly get a romanticized view of what actually exists for them if they travel to the conflict zones," she said.

"I think they think they are going to be put on a pedestal and treated very well once they are overseas, but the reality is, that's not the case."

Earlier this week Prime Minister Tony Abbott said dual nationals linked to terrorism would be stripped of their Australian citizenship.

Australia raised its threat level to high last September and has since carried out a series of counter-terrorism raids, with several alleged plots foiled this year.