Putin throws down the gauntlet - takes aim at US, calls Poroshenko a ''puppet" of the US.
The FSB said that it had eliminated a spy ring organized by the Ukrainian Defense Ministry in Crimea, detaining both Russian and Ukrainian nationals involved in preparing terrorist attacks on the peninsula.
"An agent network [created] by the Ukrainian Ministry of Defense's Main Intelligence Directorate has been eliminated. Ukrainian and Russian nationals involved in the preparation of terrorist acts have been detained and are confessing," the FSB said in a statement.
The Federal Security Service also said it had prevented two overnight attempts by Kiev-organized terrorist groups from entering Crimea.
Russia’s border with Ukraine has been reinforced and security at places of mass gathering and key infrastructure facilities in Crimea has been stepped up.
"Additional security measures in public and recreational places have been adopted, including the protection of critical infrastructure. The boundary regime on the border with Ukraine has been strengthened,” the FSB said.
A criminal investigation has been opened into an attempted act of terrorism filed late last week and claimed to be directed by the Ukrainian Defense Ministry's intelligence service, it added.
The Federal Security Service also said it had prevented two overnight attempts by Kiev-organized terrorist groups from entering Crimea on the night of Monday, August 8, in which one Russian soldier was killed.
"The break-through attempts were covered with massive shelling from the neighboring state and the Ukrainian Armed Forces' armored vehicles. A Russian Defense Ministry serviceman was killed in the firefight," the FSB said.
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