Gold bars (illustration)
Gold bars (illustration) Thinkstock

Two men who claimed last month that they discovered a Nazi-era train laden with gold may face prosecution, Polish media revealed late Thursday - over a paperwork issue. 

Last month, the two men sparked a gold rush by claiming they had found a tunnel in Walbrzych that contains a Nazi train that could be carrying valuables. 

But the treasure-hunters - Piotr Koper, a Pole, and German national Andreas Richter - did not apply to government offices for permission to use the equipment in making the find, i.e. a ground-penetrating radar (GPR). 

Lower Silesia's Conservator of Monuments Barbara Nowak-Obelinda has filed charges against the two to the District Prosecutor's Office in the city of Wałbrzych, Radio Poland reports, alleging the two were required under law to gain approval to use GPR prior to the find.

Just weeks ago, the treasure-hunters applied to the same office asking for 10% of the profits from the "Nazi gold" train. But it is unclear whether the find is real or not; Poland pledged it would deploy the military to look for the train that has sparked global fascination.

The outcome of the case - both whether the train is real and whether its discoverers will be charged for it - could set a precedent for future treasure-hunters. 

Two weeks ago, another Polish explorer claimed to have found a network of tunnels also used by the Nazi regime - this time, part of the "Riese" (giant) system of railway tunnels, corridors and shelters that the Nazis were building during World War II in the mountains around the city of Walbrzych, which were used to protect thousands of people.