Ukrainian post office announces it's preparing to print stamps showing the 'Crimean bridge -- or more precisely, what remains of it'

Official stresses that Ukraine alone decided to target and sink flagship of Russia's Black Sea Fleet using its own anti-ship missiles

Announcement is Russia's first admission of losses following ship's destruction, apparently at the hands of Ukraine's military

Pictures, video show ship listing to port with smoke pouring from damaged superstructure, life rafts missing and no sign of crew on board