Treasure hunters have started digging for 10 tonnes of Nazi gold at an 18th century palace in southern Poland.

Led by the Silesian Bridge Foundation, the dig in the village of Minkowskie is concentrating on an old orangery in a small area of the 14-hectare palace park. 

It is thought treasures, stolen on the orders of SS boss Heinrich Himmler to set up a Fourth Reich, are buried there.

A team of specialists will carefully remove layers of earth by hand as it is also being treated as an archaeological site to uncover the foundations of the orangery.

Roman Furmaniak from the Foundation said: 'We know we are looking in the right place because the foundation spoke several times to Inge before she died and she told us to look here.

'We will dig to a depth of 5 metres. The site was secured by specialists 75 years ago, so we need specialists now to uncover it.'

He added that they may find five French prisoners of war who are said to have been murdered immediately after helping to dig the hiding place.

The location was revealed by secret documents - an SS officer's diary and a map -  that the treasure hunters received from the descendants of officers belonging to a secretive lodge dating back over 1,000 years.

Among the bundle of documents is a letter from a senior SS officer calling himself von Stein to one of the girls who worked at the palace and who later became his lover.

The officer wrote: 'My dear Inge, I will fulfil my assignment, with God's will. Some transports were successful. The remaining 48 heavy Reichsbank's chests and all the family chests I hereby entrust to you.