We have this sad kind of news allmost weekly here,
A total of 440,000 bombs were dropped on Berlin between 1942 and 1945. On average 5% of them failed to explode. That means that 22,000 duds were left buried beneath the rubble. They're still being uncovered on an almost weekly basis just in & around Berlin alone.
16.Mar.2004 two unexploded WWII bombs, were discovered underneath the building site of Munich's new football stadium, the Allianz Arena. 25 Kg of TNT each. They had to be detonated in a controlled explosion.
22.Mar.2005. It was in the Paul-Heyse-Strasse near the Hauptbahnhof (Munich). An M103 flying bomb. Still live. Neighbouring streets had to be closed while the bomb was defused.
6.Feb.2006 the S-Bahn line between Munich Hauptbahnhof and Pasing had to be closed for half an hour while an American "5-Zentner-Fliegerbombe" flying-bomb was made safe.
23.Oct.2006 Monday morning at a construction site on the Autobahn A3 close to Aschaffenburg. A construction machine was planing the road surface to a depth of approximately 30cm. The driver seems to have detonated the bomb, sustaining fatal injuries, destroying the machine and tearing a crater measuring several meters wide.
and so on even after 60 years, imagine that...