Anton Kuprin, the captain of the Moskva flagship that sank in the Black Sea. Pic: Russian Ministry of Defence Ukraine has claimed the captain of a Russian warship that was sunk in the Black Sea died on board.Anton Gerashchenko, an adviser to Ukraine's ministry of internal affairs, shared the claim on Telegram saying that the ship's captain, Anton Kuprin, died during an "explosion and fire on board".The Moskva went down as it was being towed to port in rough seas after an explosion of ammo caused a fire, according to the Kremlin.Ukraine said it had hit the ship with...