KIEV More than 10 Russian military helicopters flew from Russia into Ukrainian airspace over the Crimea region on Friday, the Ukrainian border guard service said on Friday.
It also said in a statement that Russian servicemen were blocking off a unit of Ukrainian border guards in the port city of Sevastopol, where part of the Russian Black Sea fleet is based.
Russia's Black Sea fleet had earlier on Friday denied any role in the seizure of a military airport near Sevastopol.
(Reporting By Pavel Polityuk, Editing by Timothy Heritage)
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