Australian authorities have charged three women with terrorism-related offenses following their return from Syria, where they were allegedly linked to the Islamic State group.

Two of the women face charges of crimes against humanity, specifically related to slavery offenses, according to court documents. The charges stem from their alleged activities while in territory controlled by ISIS in Syria.

A third woman has been charged with joining a terrorist organization, marking the latest in a series of prosecutions against Australians who traveled to join extremist groups in the Middle East.

The women had returned to Australia from Syria, though authorities have not disclosed specific details about when they returned or the circumstances of their repatriation. Australia has previously faced complex legal and diplomatic challenges in handling the return of citizens who joined ISIS.

The charges represent some of the most serious terrorism-related offenses pursued by Australian prosecutors, particularly the crimes against humanity allegations. Such charges are rarely brought in Australian courts and carry significant potential penalties.

Australian security agencies have estimated that dozens of Australians traveled to join ISIS and other extremist groups in Syria and Iraq during the height of the conflicts in those countries.