The city of Cologne in western Germany is undergoing a major evacuation following the discovery of three unexploded bombs from World War II. Authorities on Monday found the munitions — two 1,000 kilogram bombs and one 500 kilogram bomb, all manufactured in the U.S. — in the central district of Deutz, on the eastern bank of the Rhine.

It’s the city’s largest ever post-war evacuation.20,000 people have been evacuated following the discovery of two unexploded World War

Authorities in Cologne closed off a large section of the city center Wednesday, evacuating homes and businesses and shuttering tourist spots, as experts worked to defuse three unexploded mega-bombs from World War II.