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Ministerium für Staatssicherheit (MfS)

Ministerium für Staatssicherheit, commonly abbreviated to MfS or Stasi, was the Ministry for State Security of the former DDR (East-Germany). It was one of the most effective and repressive secret intelligence and police oranisations to have ever existed, with strong links to the Russian KGB [1].

The origin of the MfS/Stasi dates back to the establishment of the Deutsche Demokratische Republik, or DDR — the German Democratic Rebublic, GDR — on 7 October 1947, shortly after the end of WWII, in the Soviet-occupied part of Germany. At that time, the agency was known as Hauptverwaltung zum Schutz des Volkeigentums (Main Directorate for the Protection of Public Property). On 8 February 1950 it was renamed to Ministerium für Staatssicherheit (Ministry for State Security), abbreviated: MfS or Stasi. Between 1953 and 1955, the Stasi operated under the control of the Innenministerium (Internal Affairs).

During the existence of the DDR, the Stasi had files on nearly everyone in the country, but also on a number of people and dissidents in other countries. After the fall of the DDR in 1989 and the reunification of German in 1990, it became clear that a number of people and security services had tried to destroy Stasi files. Nevertheless, about 11 km of files have survived and are now publicly available through the BStU.

It is estimated that at the time of the collapse of the DDR (1989), the Stasi had 91,000 employees and 200,000 informants, the so-called Inoffizielle Mitarbeiter (IM). That is one per 50 citizens, probably the highest penetration by a security service ever [1]. The MfS was renamed to Amt für nationale Sicherheit (AfNS) at the end of 1989, and was dismantled during the course of 1990.

Stasi equipment on this website
Minox miniature and subminiature cameras Tochka-58 and Tochka-58M subminiature clockwork cameras used by the KGB (Russian variant of the Minox-A) Swiss-made Tessina subminature 35 mm camera, used by the Stasi, the CIA and several others Russian Photo Sniper (Foto Snaiper) with 300 mm telephoto lens used by the KGB Russian Krasnogorsk F-21 spy camera used by the KGB for a variety of applications Robot Star 50 clockwork camera E-120 Mini Corder and U-120 Transcriber RFT, UFT-421, body wearable surveillance radio
Tesla PR-35 (FAUN), slim-line body wearable radio for surveillance tasks Tesla PS-31, semi-portable radio with voice encoding Tesla ZO-31, radio base station with voice encoding Wired Sennheiser microphone disguised as a fountain pen Sennheiser lapel microphone Miniature microphone elements manufactured by Knowles East German wired audio bug 'Bremen 20' used by the Stasi Bulgarian telephone line-carrier bug
Travel kit with concealment area for passport and OTP Small OTP booklet used by the USSR and the DDR during the Cold War
R-353 / Proton Hungarian AK-20 spy radio set Sony ICF-2001D receiver that was used by some Soviet spies in the West M-105 AGAT DUDEK StG-1 (T-352 / T-353) one-time tape cipher machine developed in Poland Soyka (USSR)
Filin (USSR) Sinitsa (USSR)
During the existence of the Stasi, its Hauptverwaltung Aufklärung (HVA) — Main Directorate for Reconnaissance — was responsible for domestic and foreign information gathering (espionage), and for conducting covert operations in foreign countries. For most of the time (1953-1986), the HVA was headed by the mysterious Markus Wolf [2].

Covert listening devices   bugs
During the Cold War, citizens of the DDR (East Germany) were under constant surveillance of the Stasi, especially if they had political motives. After the fall of the Berlin Wall in 1989, it became clear they had 91,000 full-time employees and more than 200,000 informers. That is one per 50 citizens. Some sources even claim that the Stasi had one informer per 6.5 people [1]. At one time or another, nearly everyone had been asked to spy on their neighbours or their family members.

The Stasi was particularly interested in people who objected Communism and people with a public opinion, such as journalists and artists.

Over the years, many of them were subjected to surveillance for several weeks, months or even years. People were tailed, covertly photographed, their phones were tapped and listening devices (bugs) were sometimes planted in their homes.

The image on the right shows a sophisticated listening device – made in the late 1970s by a Bulgarian company – that was used by the Stasi.
Protective cap removed

It was one of many different devices and techniques that were used to monitor people in their homes, at their workplace or in public areas. In many cases the existing infrastructure – such as telephone lines and Cable TV wiring – was used to make eavesdropping easier and more efficient. In a bugging operation, the room or person under surveillance is commonly known as the Object, or the Target. For bugging an object, the Stasi had the following techniques at their disposal:

In addition this, the Stasi used a wide range of other techniques for their surveillance operations, such as telephone tapping, visual observation, radio interception, video surveillance, covert photography, covert recording, surreptitious entry, manipulation, compromise and infiltration.

For financial reasons, bugs were always in short supply in the DDR, which is why they had to be retrieved after a bugging operation had ended. This was particularly the case for carrier bugs (TF) and radio bugs (HF), but less so for wired bugs (NF) in prisons and (international) hotels, as these were often under constant surveillance. The various types of bugs are further explained below.

Audio bugs   NF
The first category (NF) was used in places where dedicated cabling for the bug could be installed, which could take hours or even days. Such bugs generally consist of a small micro­phone — often made by companies in the West such as Sennheiser and Knowles — and a miniature amplifier.

The bug was connected to the dedicated cable, and its signal could be monitored and recorded several hundred metres away at the end of that cable. In some cases, the monitoring point was patched to a central Stasi listening post via other infrascructure, such as a free telephone line.

When correctly installed and hidden, wired audio bugs can be extremely difficult to find. They can be embedded in a wall, with the sound port of the microphone requiring a tiny hole of no more than 1 mm. A good example of a such a bug is the Bremen 20 shown in the image on the right.
Potted 'Bremen 20' bug

The red and blue wires at the right are connected to the dedicated cable and the thicker grey wire leads to the microphone which was commonly hidden inside a plastered wall. If the sound port of the microphone was extended with a hollow pipe made of plastic or wood, the device could be embedded deeper inside the plastered wall, making it virtually 'invisible' to metal detectors.

Carrier bugs   TF
Apart from the audio bugs discussed above, the Stasi could also use the existing infrastructure of a house, an apartment building, an office, a district or even a city. The bug was then installed as a parasitic device on an existing cable, using that cable to power the device and deliver its content.

Examples of existing infrastructure are the tele­phone line, the mains power cables, an intercom system in an apartment building, a common door-opener or a central antenna installation.

Such cables are usually available in every house and in some cases even in every room. As they are primarily used for the transport of other signals, the audio from a covertly installed bug had to be hidden, or masked, in such a way that it could not be picked up accidentally. This was done by modulating the audio onto a so-called carrier wave above the audible frequency range.
Bodil-B1 interior

Once modulated, the signal was injected into the cable and picked up at a tapping point several hundred metres away, where it was demodulated, recorded and eventually transcribed. A good example of a carrier wave bug is the Bulgarian bug Bodil, which is shown in the image above.

Bodil used the existing telephone line for the transport of its intelligence. Shown here without its protective cover, it could be installed nearly everywhere, for example inside a piece of furniture, inside a wooden wall or inside the telephone connection box. The audio could be retrieved with a special receiver which was placed elsewhere in the building or in some cases even outside the target area. For long-term surveillance it was even possible to patch the signal directly to a Stasi listening post by using an additional free dedicated telephone line. Similar technologies were available to bug a room via an intercom line or via the 220V power lines of the mains AC network.

Radio bugs   HF
In the rare event that the existing infrastructure could not be used for bugging a room, the Stasi used radio bugs, also known as High Frequency (HF) or Radio Frequency (RF) bugs. As they do not depend on existing cables, they can be installed nearly everywhere, even inside a movable object.

Radio bugs can be powered from the mains, but in many cases batteries were used, which greatly reduced their life span. Once the batteries ran out, they had to be swapped and access to the object was required. This could be very risky.

For this reason, remote controlled bugs were sometimes used. When the bug was not needed, it could be turned off remotely by the operator at the listening station, saving precious battery power. This was useful, for example, during the night when people were sleeping, when no­body was at home, or when an office was closed.
At present, we do not have an example of a Stasi HF bug.

Despite popular believe however, HF bugs were only used in a minority of bugging operations, as their range was very limited and they could easily be discovered by means of a special detector. In some cases they could even be discovered accidentally by someone using the radio to tune into a broadcast station. In other cases, the sound from the bug was hidden from an (un)intentional eavesdropper by using an audio-masking technique such as subcarrier frequency modulation.

BStU   Bundesbeauftragte fur die Stasi-Unterlagen
Officially: Bundesbeauftragte für die Unterlagen des Staatssicherheitsdienstes der ehemaligen Deutschen Demokratischen Republik (DDR) — Federal Commissioner for the Records of the State Security Service of the former German Democratic Republic (GDR).
HVA   Hauptverwaltung Aufklärung
Main Directorate for Reconnaissance, a department of the Stasi, responsible for foreign and domestic espionage and for foreign covert operations.
IM   Inoffizielle Mitarbeiter
Unofficial Employee — Stasi name for civil informants, inside and outside the DDR, often recruted by means of compromise and manipulation.
  1. Wikipedia, Stasi
    Retrieved March 2017.

  2. Wikipedia, Markus Wolf
    Retrieved May 2018.
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Crypto Museum. Last changed: Sunday, 06 May 2018 - 10:35 CET.
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