Something seemed to have exploded, large enough to feel like an earthquake, and a massive crater in a cornfield was all that remained.
Was it a World War II bomb? At first, officials weren't sure. But after a day studying the crater, they said it "almost certainly" was a 550-pound dud.
Undiscovered bombs can often explode without outside forces acting on them, experts say, as their detonators decompose over time.
Old bombs are not uncommon finds in Germany and elsewhere, with hundreds found each year.
In September, a 3,000-pound bomb discovered in Frankfurt caused nearly 60,000 people to be evacuated while experts defused it.
In May, more than 50,000 people were evacuated from Hanover after bombs were discovered during pre-construction work.