A new biography reveals that Simon Wiesenthal, a man who survived the Holocaust and became a Nazi-hunter, worked for Mossad, an Israeli secret service.

The Nazi-hunter received $ 300 each month from the Israeli embassy in Vienna for decades, the Israeli historian Tom Segev writes in ‘Wiesenthal, the biography’. Wiesenthal’s codename was ‘Theocrat’.

The Mossad financed Wiesenthal's office in Vienna in 1960 and handed him an Israeli passport.

In return,Wiesenthal helped the Secret Service trace Nazi criminals.

After 1945 Wiesenthal was also active in the underground Jewish organization Bricha (Flight), which helped Holocaust survivors flee to Palestine.

According to the biography Wiesenthal tipped Mossad that Adolf Eichmann was hiding in Argentina. Eventually Eichmann, also called the architect of the Holocaust, was arrested and convicted by Israel in 1960.

However, newly discovered letters show that he was against Eichmann’s execution.

Wiesenthal, who was often threatened because of his work in Vienna, died in 2005 at the age of 96. He is buried in Herzliya, Israel.