Treasure hunters believe they may have struck gold after searching an abandoned palace.
The potential horde is hoped to include the missing 'Gold of Breslau' and priceless artworks from masters such as Botticelli, Rubens and Monet.
It was hidden by Hitler's henchmen in WWII as the Red Army advanced on the German city of Breslau – which has since become the Polish city of Wroclaw.