In the late 1980s, the FBI and the National Security Agency built a tunnel under the compound for espionage purposes, but it was never successfully exploited due to FBI agent Robert Hanssen disclosing information about the operation to the KGB.
在1980年代末期，FBI和美国国家安全局出于间谍目的在使馆大院下方修建一条隧道，但是并未成功，因为FBI特工罗伯特·汉森向克格勃透露了关于行动的消息。