The betrayal has never been solved
Somebody called the German Security Police to notify them that Jews were in hiding at 263 Prinsengracht. Exactly who that was has never been discovered. This is a question that many people still want answers to. There were certain suspicions and a first investigation was conducted in 1948. Fourteen years later, once again, an attempt was made to unravel the mystery of who was responsible for the betrayal. Yet, the mystery is still to this day, not solved.
Suspicions
Quite a lot of people must have known that Jews were being hidden on the Prinsengracht. For example suppliers of daily goods, who would have seen the large amounts of vegetables, bread, meat etc. being purchased to maintain the people in hiding. There must have also been neighbors who suspected something. After all, it is almost impossible to live with eight people in one house for two long years and go completely unnoticed.
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The first investigation
Following the war, Kleiman and the other Helpers are increasingly occupied with the question of who the betrayer was. Immediately after the end of the war, Kleiman writes a letter to the Politieke Opsporings Dienst [POD] (the Dutch equivalent of the FBI). The POD had as its task hunting down people who collaborated with the German occupier. More
New investigation
The new investigation was spurred by the tracking down of Karl Silberbauer, the SS non-commissioned officer who had led the arrests. The 1963 investigation was much more thorough than the one in 1948. Again, it pointed towards Willem van Maaren. More
Other suspects
In 1998, Melissa Müller, in her biography about Anne Frank, suggests a woman named Lena-Hartog van Bladeren as a possible suspect. Two years later, another writer, Carol Anne Lee, presents a new theory in her biography about Otto Frank. She believes the guilty party is Tonny Ahlers, an acquaintance of Otto Frank.More
NIOD investigation
In 2003, the Netherlands Institute for War Documentation investigates both theories related to the new suspects:
Lena Hartog-van Bladeren and Tonny Ahlers. Both hypotheses are carefully considered and found not to carry enough weight.More