A pensioner has started digging in Germany's western Ruhr region for the Amber Room, a priceless work of art looted by Nazis from the Soviet Union during World War II and missing for 70 years, but says he needs a new drill to help him.

Dubbed the Eighth Wonder of the World, the Amber Room was an ornate chamber made of amber panels given to Tsar Peter the Great by Prussia's Friedrich Wilhelm I in 1716.

German troops stole the treasure chamber from a palace near St. Petersburg in 1941 and took it to Koenigsberg, now the Russian enclave of Kaliningrad, before it disappeared.