The newspaper's extensive article is based on last month's testimony by William Gowen at a federal court in San Francisco, which the paper says contains "historical and political explosives."
In 1999 a suit was filed at a court in San Francisco against the Vatican Bank, the Franciscan order, the National Bank of Switzerland and others. The suit was filed by the families of victims and various organisations that together represent 300,000 WWII victims. The plaintiffs demanded accounting and restitution.
The testimony links Montini to "the theft of property of Jewish, Serb, Russian, Ukrainian and Roma victims during World War II in Yugoslavia," Ha'aretz says.
Montini, who served as the Vatican's deputy secretary of state during WWII, "was involved in the sheltering and smuggling of Croatian war criminals, such as the leader of the Ustashe movement, Ante Pavelic," as part of the extensive network known as the Rat Lines, the daily says.
Ha'aretz says that senior officials at the Vatican were involved in hiding and smuggling Nazi war criminals and their collaborators so they would not be arrested and tried.
According to secret documents that were admitted as court evidence, Pavelic was assisted in his escape by British and American intelligence services. The British allowed Pavelic and a convoy of 10 trucks that carried the stolen treasure to travel to the British occupation zone in Austria. The Ustashe brought the treasure convoy to Rome, where they put it into the hands of the Croatian ambassador to the Vatican, Krunoslav Draganovic.
The newspaper says that Draganovic also saw to hiding Pavelic and his aides in Vatican institutions and safe houses in Rome.
American military intelligence located Pavelic's hiding place in 1947, but according to a secret document Gowen wrote in July 1947, which was submitted to the court, Gowen's unit received the instruction: "Hands off Pavelic." Gowen said in his testimony that the order had come from the American Embassy.
The document, classified as top secret, says that Pavelic was receiving protection from the Vatican and that he was smuggled from Italy to Argentina on the Rat Lines. A key person in this was Draganovic, who issued false papers to Pavelic and other Ustashe officials.
"I personally investigated Draganovic, who told me he was reporting to Montini," Gowen emphasised.
After the end of the war Gowen served as a special agent in the Rome detachment of American counter-intelligence, whose role was to track down Italian Fascists, Nazi war criminals and their collaborators, including Ustashe.