In October of 1940, Gerda Ditter, a housewife and mother of two, was found strangled to death in the Berlin suburb of Friedrichsfelde. She had also been stabbed in the neck. In the previous months, three other women in the same suburb had also been attacked and stabbed although none were killed. The Kripo saw a pattern developing. But there were no witnesses because the killer only attacked at night, when the city was completely blacked out.
After Gerda Ditter was killed, two other women in the area were attacked. One was beaten unconscious but the other was strangled and thrown from a moving train on the Berlin elevated railroad, the S-Bahn. Those occurred in October 1940. On 4 November 1940, Gerda Kargoll was attacked in a blacked-out S-Bahn rail car. She was hit over the head with something heavy and thrown off the moving train. But she survived. She could tell police nothing of her attacker except for one important detail: he was wearing a uniform of the German Railway. Later the lead pipe he used to hit Kargoll over the head was found in an adjacent rail carriage by the Kripo.
The Nazi Party frowned on newspapers printing bad news so the murders got relatively little press attention until it became obvious there really must be a serial killer on the loose. Even then, many papers barely gave any coverage to the murders.
The Kripo labored under three difficulties: the blackout throughout Berlin was so effective that one could see absolutely nothing. This not only frightened people but as all observers of the era recount, once the blackout went into effect people stopped talking in regular tones of voice and just whispered. That in itself was unnerving.
The second difficulty for the Kripo was this: since it was literally impossible to see anything in the blackout, twenty or thirty people were accidentally killed on the municipal railways almost every month. Many people crossing rail tracks would be mown down by a train they never saw. Others fell off station platforms while waiting for trains. Figuring out who was murdered and who just got hit by a train wasn't so easy.
Finally, the Kripo's third difficulty was this: experienced investigators who would not join the Nazi Party or had been members of the German Socialist Party, were kicked off the police force so there was a shortage of trained men.
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