Russia v. FBI

Zach Dorfman, Jenna McLaughlin and Sean D. Naylor at Yahoo News:

On Dec. 29, 2016, the Obama administration announced that it was giving nearly three dozen Russian diplomats just 72 hours to leave the United States and was seizing two rural East Coast estates owned by the Russian government.
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Both compounds, and at least some of the expelled diplomats, played key roles in a brazen Russian counterintelligence operation that stretched from the Bay Area to the heart of the nation’s capital, according to former U.S. officials. The operation, which targeted FBI communications, hampered the bureau’s ability to track Russian spies on U.S. soil at a time of increasing tension with Moscow, forced the FBI and CIA to cease contact with some of their Russian assets, and prompted tighter security procedures at key U.S. national security facilities in the Washington area and elsewhere, according to former U.S. officials. It even raised concerns among some U.S. officials about a Russian mole within the U.S. intelligence community.