Complex sentence: On 5 May 1945, Mutschmann, as "Gauleiter" of Saxony was in Dresden and let it be known that a large-scale German offensive on the Eastern Front was about to be launched.
Split into simpler sentences: On 5 May 1945, Mutschmann, as the "Gauleiter" of Saxony, was in Dresden. He let it be known that a large-scale German offensive on the Eastern Front was about to be launched.