A new investigation has identified a suspect who may have betrayed Anne Frank and her family to the Nazis.
The Jewish diarist died in a Nazi concentration camp in 1945, aged 15, after two years in hiding.
Her diary, published after her death, is the most famous first-hand account of Jewish life during the war.
A team including an ex-FBI agent said Arnold van den Bergh, a Jewish figure in Amsterdam, probably "gave up" the Franks to save his own family.
The team, made up of historians and other experts, spent six years using modern investigative techniques to crack the "cold case". That included using computer algorithms to search for connections between many different people, something that would have taken humans thousands of hours.
Van den Bergh had been a member of Amsterdam's Jewish Council, a body forced to implement Nazi policy in Jewish areas. It was disbanded in 1943, and its members were dispatched to concentration camps.
But the team found that van den Bergh was not sent to a camp, and was instead living in Amsterdam as normal at the time. There was also a suggestion that a member of the Jewish Council had been feeding the Nazis information.
"When van den Bergh lost all his series of protections exempting him from having to go to the camps, he had to provide something valuable to the Nazis that he's had contact with to let him and his wife at that time stay safe," former FBI agent Vince Pankoke told CBS 60 Minutes.
The team said it had struggled with the revelation that another Jewish person was probably the betrayer. But it also found evidence suggesting Otto Frank, Anne's father, may himself have known that and kept it secret.
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In the files of a previous investigator, they found a copy of an anonymous note sent to Otto Frank identifying Arnold van den Bergh as his betrayer.
Mr Pankoke told 60 Minutes that anti-Semitism may have been the reason it was never made public.
"Perhaps he just felt that if I bring this up again… it'll only stoke the fires further," he said.
"But we have to keep in mind that the fact that [van den Bergh] was Jewish just meant the he was placed into a untenable position by the Nazis to do something to save his life."