Complex sentence: The group collected funds for hospital expenses as friends announced that she was in Germany and had fallen ill. Her whereabouts were not revealed because supporters feared that she might be persecuted by National Socialists, because she was both Jewish and Communist.
Split into simpler sentences: The group collected funds for hospital expenses as friends announced that she had fallen ill while traveling in Germany. They did not reveal where she was, as supporters feared that she might be persecuted by National Socialists, because she was both Jewish and Communist.