"The border service made the crew get out of cars, then they prepared protocols over [the Russian sailors] an attempt to illegally cross the border, and returned [them] to the territory of Ukraine," Vladimir Voytyuk said.
He added that the crew would stay in Kharkiv, and next week, they were expected to be summoned to court.
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On March 25, the Crimea-registered vessel Nord with its 10-man crew was detained in the Sea of Azov. Moscow has demanded the immediate release of the "illegally detained" crew and the return of the vessel to its legitimate owner.
On April 6, the crew members were fined, however, a Ukrainian court authorized the arrest of the captain with the possibility of bail.