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Kyiv says it is sending reinforcements to a Ukrainian town on the Sea of Azov, about 10 kilometers from the Russian border, after the town's mayor said separatists entered the town with support from dozens of armored vehicles.
Ukrainian security spokesman Andriy Lysenko on August 27 said government troops were being sent to Novoazovsk, two days after he claimed Russian tanks invaded southeastern Ukraine disguised as pro-Russian separatist fighters.
Lysenko said Russian artillery continued to support the battle at Novoazovsk by firing across the border from Russian territory.
He also said on August 27 that a Russian "tactical battalion" -- a battlefield command-and-control unit -- was positioned near Novoazovsk at the Ukrainian village of Pobeda.
Moscow denies sending troops into Ukraine, claiming Russian paratroopers captured by Ukrainian forces in recent days had "inadvertently" crossed the border.