The Russian defense minister said Thursday that the military was starting drills at Rostov on Don near the Ukraine border in response to Ukraine’s “military machine.” This followed President Vladimir Putin's warning that the Ukrainian army’s use of force in east Ukraine was “a very serious war crime against its own people” and “there would be consequences.” Moscow’s sharp response was prompted by a Ukraine army attack that killed up to 5 pro-Russian militiamen manning three checkpoints outside the eastern town of Slaviansk. Moscow has repeatedly warned that that it would intervene if pro-Russian citizens came to harm at army hands in Ukraine.