An Oct. 28, 1985 photo of John A. Walker Jr., being escorted by a federal marshal as he leaves the Montgomery County Detention Center in Rockville, Md., enroute to a federal court in Baltimore. He was ultimately sentenced to life in prison on espionage charges. Bob Daugherty/AP hide caption

itoggle caption Bob Daugherty/AP

This handout photo provided by the Office of the Defense Secretary (OSD), taken Aug. 19, 2014, shows a Chinese fighter jet that the White House said Friday conducted a "dangerous intercept" of a U.S. Navy surveillance and reconnaissance aircraft. Uncredited/AP hide caption

itoggle caption Uncredited/AP

This handout photo provided by the Office of the Defense Secretary (OSD), taken Aug. 19, 2014, shows a Chinese fighter jet that the White House said Friday conducted a "dangerous intercept" of a U.S. Navy surveillance and reconnaissance aircraft. Uncredited/AP hide caption

itoggle caption Uncredited/AP

A U.S. Navy P-8 Poseidon aircraft takes off from Perth International Airport during the search for Malaysia Airlines MH370. The same general type of aircraft was involved in a "dangerous intercept" by a Chinese fighter jet earlier this week off Hainan island. Reuters/Landov hide caption

itoggle caption Reuters/Landov

Vice Adm. Ted Branch, the director of naval intelligence, was one of two top officers to have their access to classified material suspended. /U.S. Navy hide caption

itoggle caption /U.S. Navy