Zehra Duman used to lead a middle-class life in Australia. Then she went through a secret transformation to become an online recruiter for the Islamic State group.

The Turkish-Australian woman left Melbourne and traveled to Raqqa, Syria. Her family was shocked to learn that the 21-year-old had gone to join the Islamic State group, which is also known as ISIS or ISIL.

She then married an ISIS fighter named Mahmoud Abdullatif. The 23-year-old man used to live in Melbourne as well, but left in 2014 to join the extremist group in the Middle East.

It was December 2014 when the marriage was declared online. Al Arabiya reported that the dowry for Duman’s marriage was an assault rifle. Duman is now known as Umm (“Mother”) Abdullatif, or Zehra Abdullatif.

Duman disclosed to her online followers that her family had not been aware of her intentions. She said that she had never made her extremist views public. She said that her mother was quite close to her. Her mother is now aware that she is never going to see her daughter again, Duman said.

Duman told potential extremists on social media to wage war wherever they were. She asked them to kill nonbelievers in alleyways by stabbing or poisoning them. She also asked them to poison their teachers. Duman added that potential militants should go to prohibited restaurants and poison large quantities of food there.

The FBI is aware of people like Duman who try to lure young people to extremism. The bureau was reported to have put on presentations at New Jersey and New York schools to stop students from getting brainwashed by ISIS.

One such presentation was held Tuesday at the Bergen Arts and Science Charter School in Hackensack, New Jersey. An FBI analyst showed ISIS recruitment videos to students and cautioned them against any potential threat. A Canadian man in the video asks people to contribute to ISIS. The man eventually died in Syria while fighting for ISIS.

“It was videos and all social media that no one is really that aware of what’s happening; how deep they go into Facebook and Twitter now,” CBS quoted senior Basik Gorkem as saying. According to the FBI, over 150 U.S. citizens, including teenagers, have gone abroad to join ISIS.