Many times in Olympic history, events around the world have overshadowed and on occasions impacted the sport itself.

This was never more true than in 1956 when the Soviet suppression of a popular in uprising in Hungary coincided with a clash between the two countries in the water polo.

David Kohn, author of the book Best and Worst of the Olympics, tells Adam Batstone how tensions and bad feeling quickly spilled over into violence in the pool.