MOSCOW - It has become something of a ritual over the past decade. Revelations of a cyberattack against a geopolitical foe of Russia, accusations from Western leaders, and then the inevitable Kremlin response: "Prove it."
Washington Post: How the Kremlin is sure to keep its fingerprints off any cyberattack
A picture taken in Moscow on May 6, 2016 shows a tower in the Kremlin complex.
