DEUTSCHKATHARINENBERG, Germany - German treasure hunters began digging Tuesday for what they say may be plunder buried by the Nazis in a man-made cavern near the Czech border.

The area’s mayor, Hans-Peter Haustein, and a man who believes he found the coordinates for the buried booty in a notebook among his deceased father’s belongings, maintain that a scan of the spot has revealed that a large quantity of metal is about 20 meters below the surface.

They believe it to be either gold or silver, based on the scan with a sophisticated metal detector.

A drilling company began boring pilot holes at one-yard intervals trying to find the entrance of the cavern, about 100 yards from the Czech border in the eastern German state of Saxony. Once it is found, the searchers are to snake a camera down into the enclosure to determine exactly what they have found.

“It can’t be iron,” Haustein said as work progressed at the site. “The computer readout clearly indicates gold.”

By late afternoon, however, the most excitement for a crowd of onlookers from the tiny settlement was a short-lived geyser of water that shot up as one of the holes was drilled.

Haustein — an amateur treasure hunter who is also a member of Germany’s parliament for the opposition Free Democratic Party — said the process could take several days.

Haustein has been working with Christian Hanisch, who found the notebook in the belongings of his father, a former Luftwaffe radio operator who died last year.

Haustein said last week that he was convinced they had found the storied Amber Room treasure but later acknowledged that, while there could be “cultural treasures” in the cavern, such as paintings or amber paneling, they are not things that show up with a metal detector.

The Amber Room — named for magnificent wall panels of golden-brown amber — was stolen by the Nazis from a palace outside St. Petersburg during World War II and has never been recovered in its entirety.

Experts have been skeptical of Haustein’s claim, pointing out that stories of the Amber Room surface regularly, only to be proved wrong, and that the Amber Room had no significant amounts of gold or silver in it.