Original documents from the 1948 Nazi war crimes trial in absentia of Laszlo Csatary, now under house arrest in Hungary, have been found in Slovakia, a historian there was quoted as saying on Friday.

"The National Memory Institute (UPN) archives in Bratislava possess a legal dossier from the death sentence of Laszlo Csatary," handed down on June 8, 1948, Zoltan Balassa told the Hungarian state news agency MTI.

The documents from the trial in Kosice, at the time in Czechoslovakia, include witness testimony stating that Csatary was a "very high-ranking political officer" in the town where he was in charge of the Jewish ghetto during World War II.

Csatary, now 97 and top of the Simon Wiesenthal Center's list of surviving suspected Nazi war criminals, persecuted people because of their ethnic origin, religion or ideology, the documents attest.

Csatary, full name Laszlo Csizsik-Csatary, "told his subordinates to be cruel to the Jews in the ghetto, and personally participated in torture," Balassa said, with witnesses saying he "regularly abused his powers".

Csatary lived in Canada after the war until being stripped of his citizenship there in the 1990s, returning to Hungary where he lived undisturbed until the Wiesenthal Center, aided by British tabloid The Sun, drew attention to his case.

The Wiesenthal Center accuses Csatary of organising the deportation to their deaths of some 16,000 Jews from the ghetto, mostly to the gas chambers of the Auschwitz death camp. He protests his innocence.

After the Wiesenthal Center's tip-off, Hungarian prosecutors began an investigation last September, and on July 18 he was arrested, questioned and put under house arrest.

He is due to appear before an investigating judge in Budapest on Tuesday.