Ukraine's acting president on Wednesday said Crimea's separatist leaders had three hours to release the detained head of the ex-Soviet state's navy or face "an adequate response". Acting president Oleksandr Turchynov said in a statement that "unless Admiral (Sergiy) Gayduk and all the other hostages -- both military and civilian ones -- are released, the authorities will carry out an adequate response... of a technical and technological nature."