Who Betrayed Anne Frank? Suspect Named After Years-Long Investigation Led by FBI Veteran

It's a mystery that has baffled historians and investigators since Anne Frank: The Diary of a Young Girl was published in 1947: Who betrayed the Jewish teenager and her family as they avoided Nazi capture during World War II?

More than 75 years later, a team led by FBI veteran Vince Pankoke has finally discovered a likely culprit: Arnold van den Bergh, a Jewish businessman, father and husband who was a member of the Jewish Council in Holland.

A book based on the investigation, The Betrayal of Anne Frank: A Cold Case Investigation (out Tuesday), details the case and how the councils were used by the Nazis to "deceive, control, and slowly destroy a community," pitting Jews against Jews in the shadows of genocide.

"In 1939, in the newly occupied countries and in the Jewish ghettos, [the Nazis] established Jewish Councils to act as filters between the occupiers and the Jewish community," author Rosemary Sullivan writes in Betrayal. "The Germans imposed directives, and the Jewish Councils were responsible for implementing them. In the Netherlands the council published its own newspaper, Het Joodsche Week-blad, which listed each new anti-Jewish decree out of the eye of the general public. Had the decrees been published in a newspaper of more general circulation, the Germans would have risked an adverse reaction from non-Jews."

According to investigators, van den Bergh participated in the council in order to avoid being sent off to a concentration camp and killed in a gas chamber. (About 6 million Jews died as a result of the Holocaust, according to the United States Holocaust Memorial Museum.)

While van den Bergh was able to leverage his position on the council to live freely in Amsterdam, the book claims, Anne and her family were holed up in an annex in the back of the factory where her dad had worked. With the help of employees who brought necessities, the Franks lived in secret for 761 days, from 1942 to 1944, staying as silent as possible to avoid being caught.

During those perilous times, Anne would write about her experiences in her diary. The 15-year-old's last entry was dated Aug. 1, 1944 — three days before police raided the factory and found the Franks.

Giving up fellow Dutch to the Nazis was a criminal offense in the Netherlands, so following the war, police there twice investigated the crime in search of a suspect, only to come up empty-handed. Countless independent investigators failed as well.

But in 2016, Pankoke came to the case armed with his FBI expertise and more: funding from the city of Amsterdam and the book deal; an investigative team that included a psychologist, a criminologist and archival researchers; plus an artificial intelligence database, which the team employed to sift through years of Dutch records and rule out potential suspects.

"It would identify relationships between people, addresses that were alike," Pankoke said on Sunday's episode of 60 Minutes, which takes viewers inside the years-long effort. "We were looking for those connections. Clues to solving this."

Though there was speculation that the Franks may have been betrayed by neighbors or someone in the factory, investigators zeroed in on van den Bergh after learning that he had been in Amsterdam during the later years of the war.

"We know from history that the Jewish Council was dissolved in late September of 1943 and they were sent to the camps," Pankoke told CBS' Jon Wertheim. "We figured, well, if Arnold van den Bergh is in a camp somewhere, he certainly can't be privy to information that would lead to the compromise of the annex."

Then there was a letter that Pankoke called not quite "a smoking gun" but "a warm gun with the evidence of the bullet sitting nearby." Pankoke said the son of a detective on the Dutch police's 1963 probe gave him a copy of an anonymous note once sent to Anne's dad, Otto Frank — the only family member in the annex to survive the Holocaust.

In the letter, van den Bergh was identified as the person who betrayed the family, Pankoke said.

"In his role as being a founding member of the Jewish Council, [van den Bergh] would have had privy to addresses where Jews were hiding," Pankoke explained on 60 Minutes. "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."

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Pankoke admitted on 60 Minutes that "there could be some reasonable doubt" that van den Bergh was indeed guilty, noting that the evidence available all these years later likely wouldn't get a conviction in modern-day courts, which "want positive DNA evidence or video surveillance tape."

However, he told 60 Minutes that the motive — survival — was clear.

"I'd call him a chess player," Pankoke said of van den Bergh, who died in 1950. "He thought in terms of layers of protection, by obtaining different exemptions from being placed into the camps."

Anne and her family paid the cost when they were sent off to the Auschwitz-Birkenau concentration camp.

"On September 4th, 1944, the last transport went to Auschwitz," Otto, who died in 1980, told 60 Minutes in 1964. "Well, when we arrived at Auschwitz there were men standing there with clubs — women here, men there. We were separated right on the station, so women went to Birkenau Camp and we went to Auschwitz Camp from the station and I never saw my family again."

Anne's experiences hiding in the annex live on in her diary, which Otto turned into a book in 1947, two years after the Allied forces defeated the Nazis. More than 30 million copies of the diary have since been sold.

"I think right after the war people were shown the concentration camps, the atrocities that took place, the horror," Thijs Bayens, a Dutch documentarian who urged Pankoke to take on the cold case, told 60 Minutes of Anne's impact. "And, suddenly you find this innocent, beautiful, very smart, funny, talented girl. And she as a lighthouse comes out of the darkness. And then I think humanity said, 'This is who we are.' "

Menachem Sebbag, an Orthodox rabbi who advised Bayens, told 60 Minutes that he believes the investigation's conclusion will serve the greater good.

"I hope that people will understand that one of the things that the Nazi ideology did during the Holocaust was to dehumanize Jewish people," Sebbag said. "And going back into history and looking for the truth and attaining truth is actually giving the Jewish people back their own humanity. Even if that means that sometimes Jewish people are seen as not acting morally correct. That gives them back their own humanity, because that's the way human beings are when they're faced with existential threats."