The 3,968-pound bomb was filled with 1.5 tons of TNT, causing city officials to order the evacuation of a 1-mile radius around the explosive, Bild reported.
Pyrotechnician Rainer Woitschek helped diffuse the bomb.
"It is a big challenge in this size. But the three detonators are the familiar percussion fuse," he said.
2014: The Year in Music [PHOTOS]