Five of the women aged 18 to 29 were successful in completing their journey from Melbourne into conflict-torn Syria, the new Victoria Police counter-terrorism task force said as cited by The Herald Sun. Four of the women were deported from Turkey, one was apprehended by Australian customs agents, while two others remain unaccounted for.
"I suspect there are more than 12, but these are the ones we have a good understanding of," Assistant Commissioner Tracy Linford said as quoted by the outlet.
"Our intelligence tells us these women are going over there to meet their partners, to marry somebody in an arranged marriage or be pushed into sexual servitude," Linford told the publication.
Australian intelligence agencies estimate there are 100 Australians fighting in Syria, Iraq and elsewhere in the Middle East. A further 150 Australians are thought to be supporting foreign fighters financially.
The Australian government is preparing legislation stripping dual nationals fighting alongside or supporting Islamist militant groups of Australian citizenship.