Post by National Counterintelligence and Security Center

A cautionary #ValentinesDay counterintelligence tale: Principal Deputy Assistant Secretary of State Donald Keyser was one of the State Department’s top China experts. But he had a secret. He was having an affair with Isabelle Cheng, an intelligence officer with Taiwan’s National Security Bureau. In 2004, Keyser was arrested by FBI agents, who found more than 3,600 classified documents in his home. In 2005, he pleaded guilty to unauthorized possession of classified documents and lying about his relationship with Cheng and a trip he had made to see her in Taiwan. #nationalsecurity #intelligence #counterintelligence