sentences:  These workers, many of whom had been brought in by the Bremen Gestapo worked not only on the West Wall, but also on other military infrastructure projects such as air bases in Mannheim and in Mainz.On July 1, 1940, the camp was placed under the jurisdiction of the Inspector of Concentration Camps.After the invasion of the Belgium, the Netherlands, Luxembourg and France in 1940, Hinzert also became a prison camp for political prisoners from those countries who needed to be "re-germanised" or who were placed under "Schutzhaft".