Federal police, customs
The German federal police protects Germany's borders. As a refugee you surely will have met federal police officers on your way to Germany, when you were registered at the border, at the train stations or at the airport.
You can recognise customs officers rather easy, as they are wearing blue uniforms. They are responsible for fighting the smuggling of goods at border entries and exits, as well as illegal employment (undeclared work).
You can reach the federal police under the following phone number: 0049 800-6 888 000