A Syrian woman believed responsible for helping to deliver hundreds of young European girls to ISIS has defected, and is now warning young women of the hell that awaits them in the black-clad Islamist army's so-called caliphate.

“You are young," the defector, who used the alias Um Asma in an interview with German newspaper Bild am Sonntag, told young women considering running away to join ISIS. "The caliphate is not what you think it is. Women are whipped, sold and stoned. Corpses are on display publicly for weeks.”

"The caliphate is not what you think it is. Women are whipped, sold and stoned."

- Um Asma

Asma described her efforts as a member of the women’s terror group al-Khansa, named after a 7th century female poet who converted to Islam and wrote odes to dead Muslim fighters. The 23-year-old wore a full covering niqab that shields everything but her eyes in the interview, and used the alias because she fears ISIS retaliation. Before the outbreak of the Syrian war in 2011, she said, she wore “entirely normal clothes, had Christian friends, listened to music and went dancing.”

But after ISIS conquered Raqqa in 2013, she said she joined in order to survive. Al-Khansa, which believes women can marry jihadists as early as age 9, and advocates a frighteningly misogynistic view of their role in Islamic life, picks up the women and girls on the Turkish border and takes them to Raqqa, the de facto capital of ISIS caliphate.

Asma said her brigade sometimes took 50 girls at a time from the Turkish border into Syria. Many of the girls were from Germany, France and the United Kingdom, she said. Once in Syria, newly arrived girls receive a four-week training course, including use of firearms and study of the Koran.

The bombshell interview struck a chord in Germany, which has become a leading European hotspot for luring women and girls to serve ISIS. 

Of the 700 Germans who traveled to Syria and Iraq in recent years, about 100 are female, a German government intelligence source told FoxNews.com.

“Islamic State’s propaganda is skilled and 13-year-old and 14-year-old girls find it cool and think it could lead to a romantic marriage," the source told FoxNews.com. "They are very naive.”

It was not clear if Asma was interrogated by European authorities. Germany’s domestic intelligence agency declined to comment.

Germany has long been fertile ground for Islamic State recruitment, largely because the short flight distance to Istanbul and the lack of visas required by Turkey for Europeans.

The German rapper turned Islamic State propaganda master and Jihadi butcher “Deso Dogg,” now known as Abu Talha al-Alman, uses the Internet to radicalize young Germans. The U.S. designated al-Alman a “global terrorist” in February, and FoxNews.com reported at the time that the FBI had infiltrated al-Alman’s inner circle by using a female spy to marry him.

In the Bild interview, Asma was shown a picture of 15-year-old Leonara, a German girl who left home for the caliphate in March after being radicalized via the Internet. Asma, who acknowledged helping the girl travel from the Turkish border city of Gazientep to Raqqa, said the girl won’t return “alive” to Germany.

Benjamin Weinthal reports on human rights in the Middle East and is a fellow at the Foundation for Defense of Democracies. Follow him on Twitter @BenWeinthal