Workers digging on the underground network in the western city of Duesseldorf have uncovered a 34-kilogramme (76-pound) woolly mammoth tusk over 10,000 years old, city officials said on Tuesday.
Excavation work was stopped immediately while the 1.20-metre-long tusk was gently removed and taken away for scientific study, Duesseldorf authorities said in a statement.
The tusk was the only part of the animal found during the dig some 12 metres below the surface.
Woolly mammoths died out in the region around present-day Germany some 10,000 years ago.
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