Russia deploys advanced S-400 air missile system to Crimea: agencies

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The announcement comes two days after President Vladimir Putin promised to take counter-measures after what he said were clashes between Russian forces and Ukrainian saboteurs in northern Crimea.

Ukraine denies the clashes took place. Russia annexed Crimea from Ukraine in 2014.

(Reporting by Polina Devitt; Writing by Maria Tsvetkova; Editing by Andrew Osborn)