More than a dozen young women from Melbourne have fled to conflict zones to support Islamic State militants, and in some cases, become jihadi brides, Victoria Police believes.

Five of the 12 women are known to have successfully joined the terror group in Syria - the others were either turned back or are unaccounted for, police say.

The women are mostly aged between 18 to 20 years of age, and had lied to their families about their intentions before leaving Australia.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 4 minutes 25 seconds 4 m 25 s Listen to Simon Lauder's report. Download 8.1 MB

Victoria Police Assistant Commissioner Tracy Linford told AM she was concerned some of the women had been pushed into sexual servitude in Syria and Iraq.

"We want people to understand that it's not just a phenomenon of young men wanting to travel over to the conflict zone and join ISIS, there are women that are being lured there as well," she said.

Assistant Commissioner Linford said most of the women had a "romanticised" view of what life was like in a conflict zone.

"[They think] that they'll go over there and life will be really good for them, that they'll be put on a pedestal," she said.

"The reality is the information that we're getting back from overseas is that the lifestyle's not so good at all.

"We've had information come back that some women have actually been pushed into sexual servitude, the living conditions can be very tenuous for a young women over there, they can be on rations and living in squalid and dirty conditions."

She urged family and friends to pay attention to young women, as well as young men, who might be showing changed behaviour or disengaging from their normal family and friendship circles.

"Some of the families have contacted us, some of the families were taken by surprise when their daughters said they're travelling for some other purpose and then they subsequently find out that they've gone to the conflict zone," she said.

"In other cases, we've seen women who have succeeded in getting overseas and into those zones and have actually reached back through social media and sent messages letting their family and friends know where they are."

Assistant Commissioner Linford said it was difficult to quantify the exact numbers involved but Victoria Police knew of at least 12 who had tried to travel to the conflict zones, at least five who had succeeded and a few others they were still unsure about.

"But we suspect the numbers are probably greater than that ... I do suspect that there's more than 12 that have actually gone over to support other jihadi fighters," she said.

She said it was estimated that 30 young men had travelled from Victoria to join Islamic State.

Taskforce Pax to help monitor national security threats

Assistant Commissioner Linford heads the Security and Organised Crime Intelligence Unit and is overseeing Taskforce Pax, a new team set up to monitor Victorians who may pose a security risk.

The taskforce will work with existing counterterrorism squads and is designed to developed more information about people linked to terrorism activity.

Calls to terrorism hotlines have increased ten-fold recently and the newly formed squad will be charged with assessing that information.

"The teams will provide us with a much better picture in relation to persons who may pose a security threat to Victoria," she said.

The taskforce includes two psychologists.

"There are occasions where there could be a range of factors that might actually cause a person to think radically or behave radically or do some sort of preparatory act that could be risk to the community," she said.

"By having a psychologist on board they can actually assess all of the different things that might be going on in the lives of a person that we would class as a person of interest and they could give us some advice on that."