"We can confirm that three German children who were being held in northern Syria were able to travel to Iraq with their mother today. To our knowledge, all of them will travel on to Germany from there," a foreign ministry source told AFP.
The foreign ministry did not identify the IS suspect, but Spiegel magazine named her as Laura H., 30.
The weekly reported that the ministry were able to secure her return after weeks of negotiation with the help of an American aid organisation.
According to the magazine, German authorities had been investigating the suspect since 2016 on suspicion of belonging to a terror organisation and neglect of her children.
H. is believed to have travelled to Syria from Giessen in western Germany in March 2016, and to have joined IS that summer.
She and her children have reportedly been held in the notoriously overcrowded Al Hol camp in northern Syria since December 2018.
The camp, which is run by the Kurdish militia YPG, hosts more than 70,000 refugees from Iraq and Syria and is the subject of continuing concern from aid agencies.
German security sources believe that around 80 German IS members are still in Syrian camps or prisons.
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