Reminds me of the bugging of the new embassy in Moscow. A fun read about it in Air and Space Forces Magazine: Cleaning the Bug House.
...“Mr. Ambassador, these are the plans that disclose how the bugging of your embassy took place, and these are the instruments that were used,” said Bakatin. “I want them turned over to your government, no strings attached.” Strauss was dumbstruck, according to an account of the incident he gave later that year. After years of denial, the Soviet intelligence arm was admitting its role in one of the most notorious espionage incidents of the 1980s: It had packed the new US Embassy office building in Moscow with sophisticated listening devices. The edifice’s structure was so riddled with bugs that some US counterespionage experts described it as nothing but a giant microphone.