In 1949 advancing Communist forces trapped the British naval vessel H.M.S. Amethyst in this river
Amethyst (1957) is a British war film that 
tells ... On 19 April 1949, the Royal Navy frigate HMS Amethyst sails up the 
Yangtze River ... Before they can leave, however, the local Communist official 
Colonel Peng ... Encountering an obstruction in the river in the form of several 
sunken ships,... [DOC] [TLE] Yangtse Incident: The Story of H.M.S.