The dog – a boxer – was out for a stroll on Sunday with a 40-year-old neighbour and her white German Shepherd in the Neandertal valley – known for the discovery of the eponymous Neanderthal prehistoric skull specimen found there in 1856.
“The two dogs were playing off leash when the boxer – a normal family dog called Boogie, as in ‘boogie woogie' – found an object and brought it to the woman,” Erkrath police spokesman Ulrich Löhe told The Local.
The woman immediately recognised the object and commanded the dog to set it down, which Boogie did admirably, though she is not especially well-trained, Löhe added. Meanwhile the woman called police and waited by the grenade so that others wouldn't be endangered.
Officers from the explosive ordnance disposal unit secured the object at around 6:20 pm and identified it as a live American hand grenade from WWII. They transported it to their headquarters where it will be defused or detonated, Löhe said.
“We have at least one or two old unexploded ordnance calls in our county each month – we wouldn't have the ordnance clean up unit if we didn't need them,” Löhe said. “They are responsible for the entire Düsseldorf area, and they have a lot to do.”
Erkrath, in the rural district of Mettmann in the state of North Rhine-Westphalia, did not have any significant battles during the Second World War, he said.
"But many soldiers likely tossed their weapons aside in the area as the war ended and they made their way home," he added.
More than 60 years after the end of World War II, weapons recovery remains an important task for police throughout Germany. Allied forces dropped more than 2.7 million tonnes of explosives across Germany during the war. Some of the ordnance did not explode and has become increasingly dangerous with time and corrosion.
Entire neighbourhoods are frequently evacuated for bomb removal, and most are safely defused. Construction and road workers are trained to call emergency services the moment they suspect they've found unexploded ordnance, but accidents still occasionally happen.
In 1994, three construction workers were killed and eight bystanders injured when an unexpected bomb detonated, tearing through nearby buildings and cars in Berlin. In 2006, a road worker was killed near Frankfurt when his excavator hit a bomb.