The incident happened in Ohrdruf, a city in the state of Thuringia.
While “fishing” with a magnet, three children were shocked to realise that they'd caught several pieces of World War II ammunition and bullet fragments.
Local authorities secured the area.
Police cautioned against "such recreational activities" and urged people to immediately alert the police if suspicious object were found.
Fortunately, nobody was injured.
In June, around 3,000 people were evacuated from their homes in Berlin while a World War II bomb was defused in the centre of the German capital.
Earlier, almost 1,600 people were evacuated on 17 February in Paris due to an operation to deactivate a WWII bomb uncovered in the northern part of the city.