FRANKFURT, West Germany (AP) _ New evidence has prompted prosecutors to investigate whether Nazis killed retarded children during World War II, a newspaper said Friday.

According to the Frankfurter Rundschau newspaper, historian Karl Teppe has found evidence that 3,000 mentally retarded children were killed in Dortmund area hospitals after undergoing Nazi experiments between 1939 and 1945.

Dortmund chief prosecutor Klaus Schacht was not in his office Friday and could not be reached for comment on the report.

The Nazis' fatal experiments on people are part of the historical record, but the newspaper said the killings uncovered by Teppe were not previously known.

Teppe, of Muenster, uncovered the evidence while looking into the wartime operations of seven hospitals, according to the newspaper.

One of the institutions was the Dortmund-Aplerbeck hospital, which now is the Westphalia Clinic for Psychiatry.

Officials there were shocked by Teppe's conclusions and have started their own investigation, the newspaper said.

It quoted clinic official Annette Jedwabski as saying: ''The doctors and nurses who work in the clinic today are all with certainty free from blame.''

But she added, ''We cannot just let this drop, especially since there are many patients here who themselves certainly would have become (Nazi) victims.''

Schacht is worried the investigation could be hindered by the length of time that has passed since the end of the Nazi era, the newspaper said.

''It is suspected that many documents have disappeared since 1945, and it is still unclear who among the responsible doctors and nurses is still alive,'' according to the newspaper.

An estimated 6 million people were murdered in the Nazi Holocaust.

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