Germany today successfully defused a massive unexploded World War II-era bomb it found in a depleted riverbed in Koblenz, reports the AP, after having evacuated some 45,000 residents. The 1.8-ton bomb could have wreaked serious damage if it exploded. Experts also defused a 275-pound American bomb found alongside it. Before work began, officials went door to door today, checking for residents who had failed to evacuate. Finding unexploded devices is fairly common in the city, which was shelled during the war: 28 other bombs have been uncovered in the past dozen years alone.