Local media have for days been abuzz with old lore of trains full of gold and jewels stolen by the Nazis after two men -- a German and a Pole -- claimed to have found an armoured train car in the southwestern city of Walbrzych.
"I saw a good quality ground-penetrating radar image showing what the train looks like," Deputy Culture Minister Piotr Zuchowski told reporters, adding that he could make out platforms and gun positions on the photo.
"I'm more than 99 percent sure such a train exists, but the nature of its contents is unverifiable at the moment," added Zuchowski, who is also the national heritage conservation officer.
Friday's revelations elicited a response from the World Jewish Congress (WJC) regarding the mystery contents of the train.
"If any of these items were stolen from Jews before they were murdered, or sent to forced labour camps, every measure must be taken to return them to their owners, or their heirs," WJC CEO Robert Singer said in a statement.
"In case no survivors or heirs can be found, any gold or other property that is found to have belonged to Jewish families or businesses must now inure to the benefit of Polish Jewish survivors."
Zuchowski said the two men who discovered the train and who wish to remain anonymous, have the right to claim a finder's fee of 10 percent of the value of the train's contents.
"The fact that this train is armoured suggests there could be valuable objects inside" including artwork, archival documents or treasures, he said.
But he also warned that the train could be booby-trapped, refusing to reveal its exact location.
"My understanding is that no one has accessed it since the war."
He said someone who had been involved in hiding the train, which is over 100 metres (330 feet) in length, had passed on the information by word.
"This person shared the information on their deathbed along with a sketch of where it could be found," he said without revealing the person's identity.
Rumours of two special Nazi trains that disappeared in the spring of 1945 have been circulating for years, capturing the imagination of countless treasure hunters.
The lore has its basis in the existence of secret underground passages near Walbrzych — including around the massive Ksiaz Castle -- that Nazi Germany ordered built and where legend has it the Third Reich stashed valuables.
However, according to the Forbes magazine website, several high level sources are now claiming that the treasure has already been uncovered and is now under protection as experts sift through the bounty.