Mother lode: If the looted artworks are found in a mine, it will not be the first such discovery. In this picture from 1945, General Dwight D. Eisenhower, centre, inspects paintings uncovered in a salt mine at Merkers, Germany
Some of his pictures are still hanging on museum walls to this day, their ownership disputed by his heirs.
But most of the Hatvany Collection, between 250 and 500 pieces, was looted on the orders of Holocaust organiser Adolf Eichmann, who was in Hungary in 1944 and instituted a policy of arresting Jews and then releasing them in exchange for property.
Pillage: Nazi SS Lieutenant Colonel Adolf Eichmann, who ordered the looting of the Hatvany collection
With the permission of the mayor of nearby Deutschkatherinenberg, Hans-Peter Haustein, he deployed a neutron generator inside the mountain to probe for the secret chambers.
Mr List said: 'In the winter of 1944 - 1945 the records indicate that a mysterious transport arrived here from Budapest that was coded top secret.
One of the photos yielded up by the archives was of the Sonnenhaus, a large building directly in front of the Fortuna mine where I believe the art is stored.;"
"'It shows a large contingent of SS. There was no military or logical state purpose for them to be here on a secret mission, unless it was to deliver the artwork into chambers which, climactically, are ideal for the storage of art.'
"So far the explorations have yielded only a Schmeisser machine gun, a Nazi gas mask, plastic explosive detonators and a safe deposit key.
French master: Cezanne's La Chaine De E'toile Avec Le Pilon Du Roi, which is displayed in Glasgow and may have been looted by Nazis. More Cezannes are among the masterpieces thought to lie hidden in the mine
"Mayor Haustein, who is also an MP for the FDP liberal party in Berlin, said: 'The question is not what we find here, but when we find it."
"I have seen the evidence and I have heard the testimony of eyewitnesses over the years about the presence of the SS in the village. This stuff is here.'
"The Sonnenhaus is already drawing visitors ahead of a planned May descent into the mountain that will attempt to open up the secret chambers accessed so far only by radar.