C. Wiebes - Intelligence en de oorlog in Bosnië 1992-1995. De rol van de inlichtingen- en veiligheidsdiensten - Engels

225Naturally the Serbs had taken precautionary measures to prevent eavesdropping. To give oneexample, they used – and still use – ‘one-time pads’ for their most secret and most importantcommunications. These are number or letter codes which are used only once and are thus very difficultor impossible to crack, even for the NSA. This has led to other methods of breaking the codes:increasingly often, clandestine operations are carried out in which specialists of the CIA (abroad) andthe FBI (in embassies and consulates in the United States) penetrate a building to place monitoringequipment in the code room or to copy encryption software. This type of special operations has seen astrong growth in recent years as it is an easier way to gather intelligence than breaking difficult codes.However reliable and sophisticated the encryption equipment may be, vulnerable points will alwaysexist. To give one example, if every night a Serb unit transmits the same sentence in code to theheadquarters in Belgrade like ‘Quiet night: nothing to report’, then sooner or later this will lead to thecode being broken. A comparable example was that all Saudi-Arabian diplomatic coded cables to theking ended with the sentence: ‘May Allah prolong your life to eternity.’ Once this is known, then everycrypto-analyst can break the code quickly. A cryptography attack is always aimed at such weak spots.The Special Collection ServiceThe only resource that the NSA and CIA were sometimes able to use was the joint Special CollectionService (SCS) of these two organizations. This unit manned special monitoring stations, which werebased, in the greatest secrecy, in American embassies. These monitoring stations were set up in speciallyseparated and closed rooms. The SCS had a monitoring station in the American embassies in Belgradeand Zagreb, 1196 and from time to time the SCS managed to achieve high-level intercepts, such as aconversation between Mladic and Perisic or Milosevic.The SCS also occasionally achieved high-level intercepts of conversations between Yugoslav1197political and military leaders. This happened sporadically however, and not in a systematic manner.The activities of the SCS usually remained unknown to the ambassador and sometimes even to the CIAstation chiefs in Belgrade, Zagreb and Sarajevo. These SCS stations produced extremely useful Comintfrom the communications traffic around Belgrade, Sarajevo and Zagreb. An US intelligence officialconfirmed that the most important intelligence derived from these Embassy Collection Sites at theAmerican embassies in Zagreb and Belgrade. There was also a SCS station in the US embassy inSarajevo; this was accommodated in separate containers at the headquarters of Bosnia HercegovinaCommand. 1198Interception of Serb communications traffic: which country knew what?One thing cannot be emphasized often enough: it was not easy for the Sigint services to intercept Serbcommunications traffic. One-time pads, the use of secure landlines or couriers hindered westernservices in their attempts to eavesdrop on Serb communications. The Special Collection Service post atthe US embassy in Belgrade was probably the only monitoring station inside the Serbian capital.Moreover, the Armed Forces operated on the mainland, not always within range of the USreconnaissance aircraft flying over the Adriatic. This made it hard to achieve a detailed and extensiveSigint coverage of (Bosnian) Serb military activities. Only when the Serbian Army operated close to theborder of, or even within Bosnia, and communications traffic increased strongly, did the NSA manageto intercept these activities effectively. This was the case shortly before the attack on Srebrenica: aroundthis time much intelligence was intercepted regarding logistical matters, such as relocation of tankertrucks, trucks and other military support. 11991196 Confidential interview (6).1197 Confidential interview (13).1198 Confidential interview (13).1199 Confidential interview (6).