Vienna (dpa) - World-famous Nazi hunter Simon Wiesenthal, who died Tuesday in Vienna aged 96, survived 12 concentration camps to assist in the arrest of over one thousand Nazis following World War II.

"Justice, not revenge" was Wiesenthal's motto,for whom not forgetting was an integral part of the Jewish faith. He tried to achieve justice for the dead by bringing their murderers before the courts, and over a period of half a century helped perhaps more than anyone else to shed light on Nazi crimes.

As head of the Vienna-based Jewish Documentation Center his goal was to inform the world of the horrors committed during the Holocaust in order that such atrocities might never be repeated.

Wiesenthal was born on December 31, 1908 in Buczacz in Galicia region, then part of the Austrian empire, now Ukraine's Lvov Oblast region. He graduated with a degree in architectural engineering from Prague's Technical University in 1932, and worked first in architecture and then as a mechanic until his arrest by Nazi troops in 1941.

He survived no fewer than 12 concentration camps to begin a systematic pursuit of Nazi criminals after World War II.

His most spectacular success was his involvement in the capture in Argentina in 1960 of the notorious Adolf Eichmann, the chief organizer of Hitler's "Final Solution", which saw the murder of millions of Jews.

In all, Wiesenthal helped to bring more than 1,100 cases against suspected Nazi war criminals before the courts. He was the holder of numerous international prizes and awards, and was one of the candidates for the Nobel Peace Prize in 1983.

His own experience of the war was marked by personal suffering and tragedy.

He and his wife Cyla, who died in November 2003 aged 95, were married in 1936. When German troops marched into Lvov Oblast in 1941, Wiesenthal managed to get Cyla, whose maiden name was Mueller, false papers using the name Irene Kowalska.

Meanwhile, he himself was arrested and sent to a concentration camp.

From 1942 to 1944, Cyla lived in Warsaw. She was then sent into forced labour in the Rhineland, her true identity remaining a secret throughout.

After Wiesenthal was liberated at the end of the war, he and his wife were reunited in late 1945, after each had assumed the other was dead. In 1946, their daughter Pauline was born.

While imprisoned in Nazi camps, Wiesenthal began to record the names of the perpetrators of atrocities. After his liberation from Mauthausen concentration camp in Austria by U.S. soldiers in 1945, he dedicated himself to the search for Nazi criminals, first with the "U.S. War Crimes Office" in U.S.-occupied Austria.

In 1947 he founded the Jewish Documentation Center, which was closed again in 1954. Because of the new threat posed by the Cold War, there was a lack of interest at the time in pursuing Nazi criminals.

Wiesenthal sent all his documents to the Holocaust research center of Yad Vashem in Israel, keeping only one case - that of Adolf Eichmann.

In 1954, Wiesenthal already suspected Eichmann was in Buenos Aires, but Israeli authorities remained sceptical. The man who organized the mass murder of the Jews was later captured in 1960, and transferred to Israel where he was tried and executed in 1962.

In 1961 Wiesenthal opened his Documentation Center again, with donations from all over the world.

Among his most spectacular cases beside Eichmann was that of Karl Silberbauer, the man who arrested 14-year-old Anne Frank in Amsterdam, and was discovered in 1963 working as a police inspector in Vienna.

In 1967, Wiesenthel tracked down the former commandant of the Nazi concentration camp at Treblinka, Franz Stangl, in Brazil, and in 1987 he was involved in the capture of former commander of the Przemysl ghetto, Josef Schwammberger, in South America.

In 1977, the Simon Wiesenthal Holocaust Center was founded in Los Angeles. Today it has several hundred thousand members and has offices in New York, Toronto, Miami, Jerusalem, Paris and Buenos Aires.

In the 1980s Wiesenthal again applied his principle of objective examination of the facts in the case of former Austrian president Kurt Waldheim.

Wiesenthal concluded that Waldheim had known of war crimes, even if it could not be proved that he had taken part in them. He said that Waldheim had "not always spoken the truth" about his past in World War II, and called on him to resign, but Waldheim remained in office unil 1992.

In his later years, Wiesenthal suffered increasingly from health problems and withdrew to his Vienna apartment, not even leaving it for the funeral of his wife Cyla in 2003.

In various comments during his long decades of work, Wiesenthal said that the memory of Nazi atrocities was "an early-warning system" against future crimes against humanity.

He had dedicated himself to "the fight against forgetting" because it was the greatest duty of his generation to protect future generations against the resurgence of Nazism.

He described his work as a warning to "the murderers of tomorrow".

"Freedom is not a gift of heaven, you have to fight for it every day," said Wiesenthal.