A German teenager who fled her home to fight for ISIS is likely to stand trial in Iraq , according to diplomats trying to bring her home.
If convicted, Linda Wenzel - who was captured in the war-torn city of Mosul - could face the death penalty.
German authorities are understood to be desperately trying to bring her back to Europe, where she could spend a decade in prison if found guilty of joining the terror group.
She vanished at the age of 15 after falling in love with a fundamentalist she met online, who she later married.
German diplomats now say Iraqi authorities have opened criminal proceedings against Wenzel, who is currently in a jail in Baghdad.
The teenager, from the town of Pulsnitz in the eastern German state of Saxony, was seized by Iraqi soldiers after the city fell in July.
She had been hiding in an underground tunnel network in the city, which had been under ISIS control since 2014.
Wenzel is one of four German women likely to be charged with terrorism and membership of ISIS.
She forged a letter from her mum in order to buy a plane ticket to Istanbul, from where she crossed into Syria. The teenager was later smuggled into Iraq.
As Germany opposes the death penalty, its diplomats regularly lobby to bring citizens home if they face being executed.
Wenzel married a Chechen fighter who was killed in combat, and when she was captured in Mosul she was carrying a malnourished baby believed to be the couple's child.
Her friends in Germany told police that she had suddenly started taking the Koran to school, and wearing longer, more conservative clothing after becoming fascinated with Islam.
Officials from the federal prosecutor's office in Karlsruhe are also investigating Wenzel and the three other women on suspicion of ISIS membership.
Pictures of her following her arrest show a startling transformation from the once healthy looking teenager she was before she fled.
Radicalised in Germany, she changed her name to Mariam and sometimes posted photos of herself wearing a headscarf.
Wenzel was among 20 Islamic State followers seized after the city fell following a ten month battle which left 25,000 Jihadists dead and Iraq's second largest city a sea of devastation.
She was said to have been unhappy at home and turned to Islam.
She soon began engaging with ISIS followers in the Middle East in internet chat rooms and was under the observation of German intelligence officials suspected of plotting a serious crime against the state when she fled abroad.
She was caught in a tunnel system in Mosul with other women, some of whom wore suicide vests and had automatic weapons.
Media reports said they worked for the Islamic State police force in the city.
Among those detained were also women from Russia, Turkey, Canada and Chechnya. All were seized during military mopping-up operations.
Linda's mother, Catherine, said at the time she vanished: "She got a proper brainwashing. I hope we can get her back."