Some of these activities were directed via the East German Stasi (Ministry for State Security). One such operation, "Operation Brunnhilde," operated from the mid-1950s until early 1966 and made use of spies from many Communist Bloc countries. Through at least 20 forays, many western European industrial secrets were compromised. One member of the "Brunnhilde" ring was a Swiss chemical engineer, Dr. Jean Paul Soupert (also known as "Air Bubble"), living in Brussels. He was described by Peter Wright in Spycatcher as having been "doubled" by the Belgian Sûreté de l'État. He revealed information about industrial espionage conducted by the ring, including the fact that Russian agents had obtained details of Concorde's advanced electronics system. He testified against two Kodak employees, living and working in Britain, during a trial in which they were accused of passing information on industrial processes to him, though they were eventually acquitted.