Training material of Department M
 

At the end of the 1980s, Department M (postal surveillance) of the Ministry for State Security (MfS) produced training material as guidance for staff on detecting explosives, weapons and ammunition. Each District Administration for State Security was given a copy, and its receipt had to be formally confirmed.

The results of the investigation showed that X-ray procedures were unsuitable for detecting explosives in postal items. In the images, it was almost impossible to distinguish between explosives and materials with a similar density. Further images showed how to detect explosives, weapons and ammunition concealed in books, technical equipment or other containers. Shoes, school bags and blood pressure monitors could also serve as potential hiding places for smuggling such items. In addition, the documents provide information on the methods used to identify ammunition and weapons.