19/06/2012 10:27 BST | Updated 19/08/2012 10:12 BST

Gitta Sereny Dead: Veteran Journalist And Author Of 'Into That Darkness' Dies At 91

Gitta Sereny, the influential journalist and author of Into That Darkness, has died aged 91.

Sereny was a veteran reporter who investigated some of the most appalling crimes and events of her time, including studies on the killers of James Bulger, the murderer Mary Bell and the Nazi concentration camp commander Franz Stangl.

The latter was the subject of her widely-praised book Into That Darkness (1974), a work that typified her tenacious approach to getting under the skin of her subjects.

Sereny devoted over 60 hours to visiting Stangl in prison in order to interview him about being blamed for the death of 900,000 people. At the conclusion of the interviews he finally admitted his guilt, but died of a heart attack hours later.

At other times, Sereny’s commitment to spending time with some of the most reviled figures of our times attracted controversy and criticism.

In 1995 she returned to the subject of Nazism to write Albert Speer: His Battle With Truth, a biography about the Nazi architect that would go on to win the James Tait Black Memorial Prize.

However, she was accused of getting to close to Speer in order to elicit information from him, including confessions that he knew about Hitler’s plans to murder Jews.

In 1998, her book Cries Unheard was criticised after Sereny revealed that she was sharing her publishing fee with its subject, the child killer Mary Bell. However, it stands up today as a cornerstone text for professionals working with problem children.

Sereny’s death was confirmed by her publisher at Penguin Press, Stuart Proffitt, who confirmed she died last week at Addenbrooke's hospital in Cambridge after a long illness.

"She was an enormously spirited person, extraordinarily brave and very, very determined," he said.

Proffitt said Sereny, who died last week at Addenbrooke's hospital in Cambridge after a long illness, had been working on new material prior to her death. He said what was intended to have been a history of Vienna had become an autobiography of the writer, but the book is too incomplete to be published.

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