They hunt for jewels and gold, the long-hidden plunder of Nazi lore. Now hobby historians in Germany believe they have an urgent case of potentially catastrophic proportions — secret nuclear bombs.

Deep inside the Thuringian Forest, 70-year-old Peter Lohr and two friends have been scanning the surface with “earth radar” and “geomagnetic” technology after one of Lohr’s companions found Allied aerial surveillance photos of what they believe is a Nazi storage facility.

“What did the Nazis really do here? There are so many unanswered questions,” said 67-year-old Walter Boegenhold, a local resident interested in military history who has heard stories about Hitler’s secret projects in the region since his teenage years.

The team’s initial surface scans produced colorful images of what appears to be bomb-shaped metal housing, which led Lohr and Boegenhold to partner with explosive ordnance disposal expert Ralf Ehmann, 60.

“After conducting geomagnetic scans and carefully looking at all the images, I believe that we have Fat Man bombs buried below the surface,” Ehmann told NBC News.

“Fat Man” was the name for the plutonium bomb dropped by U.S. planes on the Japanese city of Nagasaki in 1945. Ehmann believes a similar nuclear bomb was developed by the Nazis.

Local authorities, however, think that’s hogwash.

Officials conducted a “broad examination” after “being alerted to a suspected case of nuclear weaponry in the Jonas valley,” the city of Arnstadt said in a statement, but they later determined that there was no evidence that “would confirm the suspicion.”