(CNN) -- At first Alon Meyer thought it was a bad joke. When Kreshnik Berisha, the first suspected member of ISIS to stand trial in Germany, was arrested upon his arrival back in Frankfurt in December after spending six months in Syria, youth team football coach Meyer was left shell-shocked. The coach thought for a while and then it slowly sank in -- this was the same boy who had once stood by his side and taken the field in the shirt of Makkabi Frankfurt, Germany's largest Jewish sports club. Meyer's phone began to buzz with journalists trying to ask him whether he remembered Berisha, a 20-year-old born in Frankfurt to Kosovan parents.
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Kreshnik Berisha arrested in Germany for links with ISIS
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Berisha used to play for a Jewish football team in Frankfurt
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Club and community shocked by events
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Sentence expected to be handed down next month
It has opened its doors to everyone in the past decade, with @placeholder insisting Makkabi Frankfurt "does not talk about integration, it lives integration."