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The long-lost diary of a Hitler crony who helped exterminate millions of Jews during World War II has surfaced in an upstate New York home, promising new insights into dealings between top Nazi officials and specific information about the looting of Jewish-owned art, Reuters reported.

Some 400 pages from the diary of Alfred Rosenberg could offer new details about meetings Rosenberg had with Hitler and other Nazi leaders, including Heinrich Himmler and Herman Goering. The pages also include details about the German occupation of the Soviet Union and chilling plans for the slaughter of Jews and other Eastern Europeans. The diary vanished after the war crimes trials, and only recently turned up in papers held by a one-time secretary to a Nuremburg prosecutor.

"The documentation is of considerable importance for the study of the Nazi era, including the history of the Holocaust," according to the assessment, prepared by the United States Holocaust Memorial Museum in Washington. "A cursory content analysis indicates that the material sheds new light on a number of important issues relating to the Third Reich's policy. The diary will be an important source of information to historians that compliments, and in part contradicts, already known documentation."

Rosenberg, a Nazi Reich minister who was convicted at Nuremberg and hanged in 1946, hand-wrote his recollections from spring 1936 to winter 1944, according to the museum's analysis. Among the insights into the German high command are details about the crisis caused by Rudolf Hess's flight to to Britain in 1941, and the looting of art throughout Europe, according to Reuters.

The recovery will be announced this week at a news conference in Delaware held jointly by officials from the U.S. Immigration and Customs Enforcement, Department of Justice and Holocaust museum.

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Rosenberg directed the Nazi party's foreign affairs department, edited the Nazi newspaper and directed the systematic Nazi looting of Jewish art, cultural and religious property throughout Europe. Several memos he wrote directly to Hitler were entered into evidence at Nuremberg.

A Nuremberg prosecutor, Robert Kempner, was long suspected of smuggling the diary back to the U.S. Indeed, Kempner cited a few Rosenberg diary excerpts in his memoir, and when he died in 1993 at age 93, legal disputes about his papers raged for nearly a decade between his children, his former secretary, a local contractor and the Holocaust museum.

The Holocaust museum has gone on to recover more than 150,000 documents, papers held by Kempner's former secretary, who by 1999 had moved into the New York state home of an academic named Herbert Richardson. The Rosenberg diary, however, remained missing.

Early this year, the Holocaust museum and an agent from Homeland Security Investigation tried to locate the missing diary pages. They tracked the diary to Richardson, who was living near Buffalo.

Richardson declined to comment. A government official said more details will be announced at the news conference.

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