BERLIN (AP) -- German authorities safely defused a huge bomb left over from World War II after evacuating large parts of the western city of Dortmund on Sunday.
About 20,000 people were taken to safety before explosives experts moved in to defuse the unexploded 4,000-pound (1,800-kilogram) bomb that was discovered by analyzing old aerial photographs.
The bomb was dropped by Allied aircraft over the Ruhr region -- a key industrial center for the Nazis' war machine.
While unexploded World War II-era bombs are regularly discovered in Germany, they are rarely as big as this one.
A similar bomb find two years ago prompted the evacuation of around 45,000 people in the city of Koblenz along the Rhine river.
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