Dr Aribert Heim, who was born in Austria, murdered hundreds of Jewish prisoners at the Mauthausen concentration camp by subjecting them to gratuitous and brutal medical experiments during the seven weeks that he spent there in 1941.
Heim ranks alongside the Auschwitz doctor, Josef Mengele, as one of the most reviled Nazi war criminals. A court trying him in his absence in 1979 concluded that he "wallowed in the fear of death suffered by his victims" while performing hideous operations on fully conscious prisoners.
Now 91, he lived in Germany briefly after the war but has been on the run from Nazi-hunters since the early 1960s. Since then there have been alleged sightings of him in South America, Egypt, Spain and Germany. Until only recently investigators assumed that he was dead.
German state prosecutors in Stuttgart and the Vienna-based Simon Wiesenthal centre revealed yesterday that they had gained access to Heim's bank accounts in Berlin, which were shown to contain almost €1m (£680,000) in savings and other assets.
They said the fact that none of Heim's three children had claimed the sums on the doctor's accounts suggested that he was probably still alive. Records showed that as recently as 2001, Heim had asked that the German tax authorities pay back capital gains tax levied on him because he was living abroad.
"Heim is at the top of our list of wanted Nazi war criminals," said a spokesman for the Stuttgart state prosecutor's office. "We have no proof that he is dead either under his real name or an assumed one. We think he is still alive."
Stuttgart prosecutors said that as part of their drive to catch Heim, they had increased the reward for information leading to his arrest to €150,000 and issued a computer-manipulated photograph giving an impression of his current appearance.
Der Spiegel magazine disclosed yesterday that the hunt for Heim was also being vigorously pursued by Efraim Zuroff, of the Jerusalem branch of the Weisenthal centre, under the organisation's "Operation Last Chance", which is designed to catch the last remaining Nazi war criminals before they die. "The hunt for Heim is not over," Mr Zuroff told the magazine.
Heim worked at Mauthausen as a doctor for the Nazi SS from 8 October 8 until 29 November 1941. Camp survivors have revealed in evidence how he injected prisoners in the heart with different cocktails of lethal drugs and timed their deaths with a stopwatch to find the most efficient murder instrument.
In another case, Heim removed the tattooed flesh of a prisoner to make seat coverings for the camp commandant's private flat.
He is also accused of cutting off the head of a murdered Jewish prisoner and boiling off the flesh to enable the skull to be used as an exhibit.
At the end of the war Heim was working as an army battalion doctor, a job which appears to have allowed him to cover up his activities as a war criminal.
In the late 1940s he worked as a gynaecologist in the quiet spa town of Bad Nauheim, near Frankfurt. He married, and even played in the local ice hockey team.
The net did not begin to close on him until 1957, when the Austrian authorities started an investigation that in 1962 led state prosecutors in Germany to issue a warrant for his arrest.
A tip off by former Nazis is believed to have enabled Heim to get away from his home in his red Mercedes car shortly before police arrived. He has not been positively identified since. The only person thought to know Heim's whereabouts is Fritz Steinacker, the family lawyer. He has refused to give any information on the grounds that it would breach client-lawyer secrecy guaranteed under German law.Reuse content