Early 20th century communications interception in Spain: a historical perspective

COMINT (communications intelligence) activities involving the interception and surveillance of Spanish communications from the British colonial outpost of Gibraltar have been an integral part of British intelligence activities for centuries, particularly during the 1st and 2nd world wars, and the Spanish Civil War. In spite of Spain's neutral stance during World Wars I and II and its lack of prominence in world affairs, a chapter written by Arturo Quirantes Sierra in the book "Libertad Vigilada", published in 2003 by the journalist Nacho García Mostazo, which is based on documentation from the British Public Records Office, claims that Spain's "geographic location, its importance as a regional power and the upheavals that it experienced both within and outside its frontiers made Spain an important target for the surveillance of telecommunications". The importance of "secondary countries" in COMINT activities has been described as a "window effect", which provides a "stepping stone to get to know the movements and strategies of the leaders of other powers". This process would become particularly intense during World War II, due to the close relations between General Franco's regime and the Third Reich.

After noting that as far back as the late 16th century British agents were already intercepting and decoding messages between the Spanish emperor Felipe II and Don Juan of Austria, the Spanish governor of the Netherlands, alerting them of the emperor's belligerent intentions - thus contributing to the defeat of the Spanish Armada by the British - Quirantes documents the extent of British surveillance activities targeting Spanish communications in the early 20th century. During the first world war, the interception of coded diplomatic correspondence concerning reparations to be paid to Spain by Germany for commercial losses resulting from the submarine war declared by Germany in response to a British blockade of Germany, between the Spanish monarch Alfonso XIII and the Spanish embassy in Berlin, gave Britain access to privileged information. In this instance, the information included German plans to intensify its submarine warfare operations, and other issues including the loss and retrieval of documents from a German submarine in the south-eastern port of Cartagena, the possibility of Spain selling ships to countries involved in the war, and German concerns over the treatment of its POWs in France.

Other facets of British surveillance activities in the Iberian peninsula included the monitoring of Spanish-Portuguese relations (Portugal being a longstanding British ally in the region) and the interception of Spanish communications concerning North Africa, which gave British agents an idea about the intentions of France, its traditional colonial adversary, as well as a military advantage, as they included Spanish reservations concerning the presence and position of the British and French naval fleets in the Mediterranean. The Spanish Civil War was another conflict that attracted the interest of the British intelligence services, with the British obtaining "detailed daily updates on the situation in the conflict". Quirantes describes the breadth of information received by the RAF (Royal Air Force) alone as "encyclopaedic", including exhaustive knowledge of the location and contents of the main arsenals and bases, down to the last bomb, airplane or cartridge. The importance of these intelligence activities was heightened by the fact that the Spanish Civil War proved an important testing ground for weapons and tactics that were later to be used in World War II. For example, a message intercepted on 27 October 1936 ordered the urgent delivery of gas masks from the Nationalist Air Force General Command to the airfield in Talavera, in the province of Toledo.

The main interception centre for Spain was in Gibraltar, and it was the critical site for surveillance of Spanish communications. Communications between Ceuta (in north Africa) and Madrid were an important source of high quality information, and Gibraltar was also a suitable location from which to tap into communications between Madrid and Spanish military attachés in Rome and Berlin, a source of valuable information of a political and military nature. The base in Gibraltar was equipped by Britain with any material it needed (including keys to decipher messages and code handbooks) which made it easy to neutralise the cryptographic protection used in Spanish communications. So much so, that Quirantes claims that "the interception of Spanish communications was so simple as to become trivial" for the British, particularly in the cases of communications by telegraph or using high frequency radio signals. The British had exhaustive listings of the codes used by the main air force, navy and army bases issuing communications - this highlighted the weaknesses resulting from the lack of cryptographic tradition in Spain, while the most advanced coding machines that became available to Spain tended to be models that had already been cracked by the British. This continued to be the case when Spain obtained Enigma coding machines in the late 1930s and early 1940s. These were used by Franco's nationalist forces and by the German Condor Legion during the Spanish Civil War, but the British "Ultra Intelligence" operation was already decoding Spanish messages that were encrypted using early versions of the Enigma machine, which were inferior to those used by German armed forces, by 1937. These machines were used in communications with Spanish military attachés in Rome and Berlin, and the information gathered by British intelligence services included plans for German-Spanish industrial cooperation, the exchange of raw materials for machinery, the possibility of Spain building submarines for the Germans, and Spanish interest in obtaining material for its armed forces, such as fibre optics, torpedoes, alloys and radar systems.

The special relationship existing between Spain and Germany meant that Spain was placed under permanent surveillance during World War II, as the value of the "window effect" was augmented by the possibility that Spain might enter the conflict: a de-classified document from September 1943 states that:

"The intelligence gathered is rarely of great value in itself, but it occasionally helps other sub-sections by providing clues in messages concerning issues that interest the Spanish and Germans alike. It provided the Admiralty with useful details concerning the arrangement and activities of the Spanish fleet which, at any time, may come to be of operative value."

Another target of British COMINT operations were communications by German agents from the Abwehr (secret service), who were active in Spain conducting activities such as the monitoring of British naval movements from around the Gibraltar area. Their messages were relayed using a special type of Enigma machine, which had also already been decoded by the British. In 1941. Germany also had a communications station in Tetuán (then Spanish Morocco) to relay messages to its embassy in Madrid, stations to produce airwave interference in Pamplona (Navarre) and Madrid, and another communications centre in Seville (Andalusia) to relay messages to the German naval intelligence services in Paris. The intelligence that was gathered by the British was sent to the General Command in Gibraltar, particularly if it was relevant to the anti-submarine struggle or to operations in North Africa.

After World War II British communications interception continued within an anti-Communist framework, as part of the UKUSA agreement (which also included Canada, Australia and New Zealand) which spanned the world (and later in the 1980s included the "Echelon" network); Britain was responsible for COMINT in Western Europe and the Middle East.

García Mostazo, the author of "Libertad Vigilada", claims that UK communications surveillance operations based in Gibraltar continue today. Reports in La Razón newspaper in May 2002 quoted an unnamed navy source saying that "London possesses a great centre for electronic surveillance for southern Europe in Gibraltar". Another unconfirmed report from the same newspaper reports allegations by "sources close to the intelligence services" that the British have a system in place to tap into information flowing through underwater telephone cables in the Strait of Gibraltar, although García Mostazo argues that this has never been proven, and that the British may be unable to tap the underwater cables without assistance from the US. On the other hand, the author claims that there are two SIGINT (signals intelligence) centres in the colony, one in the north and the other in the south. The first is found in the highest point of the Rock of Gibraltar inside a site that is signposted as a "Signals Station". It includes a circular aerial that is covered by a dome, although the structure that García Mostazo describes as being "most important", is a "complex of turrets that are joined by steel cables and are used to intercept high frequency radio communications", that is found in the woods that "crown the Rock". The other military installation that appears to be devoted to espionage is in the southern part of Gibraltar, and is disguised as a civilian communications centre. Sign-posted as a "Terrestrial Satellite Station and Operation Centre", and owned by the "Afro-Asian Satellite Communication Ltd.", it is found within a fortified military enclosure, and its entrance features a UK defence ministry notice in English, Spanish and Arabic, which states that it is a restricted area subject to the Official Secrets Act, and that trespassers may be arrested and charged. It includes two large circular aerials with diameters of over 20 metres, one of which is covered by a dome. Its possible function is unclear, although the description of these aerials and the fact that the advertised "civilian satellite station" is not to be found within the enclosure, indicate that its scope may not be strictly legal. Furthermore, the presence of intelligence units in Gibraltar is confirmed by the UK army's official website, whose intelligence services "lifestyle" section speaks of the possibility to travel every few years: "There are units in Gibraltar, Cyprus, Germany and the Falklands [or Malvinas] Islands…"

1. Introductory articles on Spanish, US and UK installations, in English
2. Website of the book
3. E-mail contacts for authors: (Nacho García Mostazo, the author) and: (Arturo Quirantes Sierra, author of the chapter on the history of British communications interception in Spain)

Previous Statewatch coverage in March 2003:

Secret military telecommunications interception stations in Madrid, Conil de la Frontera, Gibraltar and Rota

"Libertad Vigilada" (Freedom under Surveillance), a recently published book by Nacho Garcia Mostazo, analyses the presence in Spain of a number of stations for the interception of telecommunications and to conduct signals intelligence operations that are run separately by the Spanish, British and US military. It focuses on two secret Spanish military intelligence establishments, one near Madrid and the other in Conil de la Frontera, near Cadiz, two military installations run by the UK military in Gibraltar, and another by the US military in its airbase in Rota, also near Cadiz. These are deemed to violate the constitutional guarantee of privacy for the telecommunications of Spanish citizens. Foreign intelligence agencies are only forbidden from intercepting telecommunications of their own nationals. In the case of domestic military intelligence structures, these are subject to less democratic control and regulation than their civilian counterpart, the newly-established National Intelligence Centre.

The Fresnedillas-Navalagamella Satellite Monitoring Station in the mountain range (Sierra) located to the north of Madrid is allegedly being used to intercept satellite communications of the countries surrounding Spain, and possibly civilian communications within Spain itself. The base is owned by the Ministry of Defence and is shrouded in secrecy. Defence minister Trillo Figueroa denies the institution's ownership of the station although it pays 11,713.52 euros annual tax on the property, and claims that activities conducted there are "a mystery". Ten large parabolic antennae with diameters of over 18 metres are found at the base, as well as six smaller ones; their inclination indicates that they may be aimed at geo-stationary telecommunication satellites hovering above the equator at an altitude of around 36,000 km. The author stresses that the European Parliamentary Commission that investigated the Echelon affair concluded that "if two or more satellite reception antennae of over 18 metres (in diameter) can be found at a (military) station, it is certain that civil communications are listened to there".

It is significant that the station is run by the military. The former Spanish intelligence agency (CESID) was run by the military, and was recently replaced by a civilian agency, the CNI (National Intelligence Centre, see Statewatch vol 11 no 3 & 4). This change was partly motivated by a lack of accountability, and of a clear legal basis for interception, that resulted in the illegal interception of Spanish citizens in the past. The CNI is subject to interception guidelines requiring a judicial warrant for the interception of communications involving Spanish citizens, which are protected from interference by the Spanish constitution, although telephone tapping was not regulated until the new law was passed last year.

The author of "Libertad Vigilada" says that the parallel activities of military structures and personnel may be used to circumvent the limitations that have been introduced. They support this notion by noting that at the same time as the CNI laws were passed, the Ministry of Defence set up the so-called Armed Forces Intelligence Centre (AFIC - CIFAS in Spanish) to enable "the process of rationalising the intelligence capabilities of the Defence, Army and Navy Staff". AFIC is not regulated by any law, other than a ministerial order specifying its internal organisation. The authors also note that a secret military project approved in 1986, and known as the "Santiago programme", is due to be fully operational by 2008. It is reportedly aimed at "capturing electro-magnetic broadcasts and images in zones defined as of strategic interest for national security". Thus, in spite of the official military intelligence agency being shut down:

"Spain has a military espionage network composed of surveillance planes (the Air Intelligence Centre at Torrejon de Ardoz), observation satellites (Helios and others that will soon be launched) and land bases - although the system is not yet complete"

A secret intelligence operation in Conil de la Frontera was set up jointly by former Spanish intelligence agency CESID and its German counterpart, the Bundesnachrichtendienst (BND), in 1975 as part of "Operation Delikatesse". It was aimed at intercepting telecommunications passing through a telecommunications station that is run by Telefonica in Conil de la Frontera, that links Spain with the Canary Islands, and other Mediterranean, African and American countries through undersea cables. In 1992, the Germans left the installation, based in a chalet and manned by military staff, as indicated by locals referring to the chalet as "house of the military" and the street name, "Camino de los Militares" (Military Way), in spite of an official absence of army installations.

The book also looks at espionage operations conducted by the US and UK in the Iberian peninsula. The US has been authorised to use bases on Spanish territory for espionage purposes since 1953, when a Hispanic-American covenant was signed to enable the construction of US military bases, of which there are two: one in Moron de la Frontera (Seville), and the other in Rota (Cadiz). The latter base has had a large antenna (with a 500 metre circumference) known as AN/FLR-13, capable of capturing radio broadcasts at a distance of over 5,000 kilometres. Members of the Naval Security Group (NAVSECGRU), the code-breaking division of the US Navy, have been stationed in Rota since the 1960s. The Hispanic-American covenant was updated on a number of occasions, and the last time, on 10 April 2002, a list of installations on US bases, such as a "naval communications station" and an "information installation for maritime monitoring", were included. The latest version of the covenant authorises the US armed forces to undertake activity in the field of telecommunications to:

"1) meet new operational requirements, 2) improve the capability of existing systems and 3) to contribute to the welfare and training of the mentioned forces"

US criminal investigation services have been authorised to conduct espionage activities in Spain, and cooperation with its Spanish counterparts is encouraged, particularly in the context of the fight against terrorism which Spain is conducting against ETA. Thus, large-scale surveillance is allowed without laws to regulate who may or may not be spied on, as constitutional guarantees only apply to nationals of the country that is doing the surveillance.
Two espionage communications posts are allegedly run by the British army on Gibraltar to listen in on communications crossing the Strait between Spain and North Africa. One is a signals station in the north part of Gibraltar, whose large antenna for intercepting radio waves, over a radius of more than a thousand kilometres, consists of a dozen metal towers joined by steel cables. The second is near to Gibraltar's southernmost point, and has two large parabolic antennae within a fortified military precinct owned by the UK Ministry of Defence. Ever since the 1970s, the UK has been intercepting Spanish communications from Gibraltar. These practices continue in spite of the UK and Spain being military allies, and the importance of the UK's military bases on Gibraltar is seen by the authors as an important reason for the two country's failure to reach a settlement over Gibraltar.

The revelations of the interception stations run by the US and UK military have important implications in view of the UKUSA cooperation involving the UK, USA, Canada, Australia and New Zealand that comprises the Echelon telecommunications interception network on a global scale which relies on the wholesale interception of worldwide communications.

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