Duisburg

"They're just normal people," said one young man of immigrant origin in Duisburg, a city in western Germany's old industrial heartland.

In last summer's European elections it won the vote in some northern areas of the city of Duisburg, with 20% in Marxloh, 25% in an adjacent area and 30% next door to that.

In the city of Duisburg in Germany’s industrial heartland is a vast steel complex that is one of Europe’s largest polluters.

By using electricity to split water into its two elements, the device, a test model called an electrolyzer, produces hydrogen, a carbon-free gas that could help power mills like the one in Duisburg.

The suspects were detained in the western cities of Duisburg, Herne and Dueren in the state of North Rhine-Westphalia, and their apartments were also searched there.