Berlin (CNN) In the summer of 2014, Danisch Farooqi says he received a phone call from his ex-wife informing him that she had taken their daughter, Aaliya, to Turkey. In a panic, he tried to get her back to Germany, he says, but within days his daughter was in Syria and her mother had married an ISIS fighter.

"I don't even know what my daughter has experienced and seen in those five years," Farooqi told CNN, tearing up at the thought. "Once you finally find your daughter, you then hope for the help of the German government to get her back. And there is none. It's devastating. It's frustrating. And I'm really very angry."

The defeat of ISIS has stranded tens of thousands of ISIS followers -- including Aaliya, now eight years old -- in Kurdish-run camps in northern Syria, but the German government has been slow to repatriate German citizens.

Earlier this week, Farooqi organized a public protest by family members, believed to be the first of its kind in the country, outside the Foreign Ministry in Berlin to demand the German government do more to repatriate its citizens, especially children, stranded in Syria. Several dozen protesters carried placards with photos of their daughters, sons and grandchildren.

Germany's Foreign Ministry would not confirm to CNN how many German nationals are now in the camps but only a handful of children born to ISIS followers have been brought back to Germany and placed with relatives. In a statement to CNN, the Foreign Ministry insists that it is "virtually impossible" to provide assistance to any of them.

Read More