The problem of violence in football is as old as football itself. The Mexican writer Juan Villoro, author of books such as Balón Dividido will talk about this phenomenon with members of organised-fan- groups from both Medellin main football teams.
Owen Sheers talks to Peter Florence
Martín Caparrós, Wojciech Jagielski and Vaiju Naravane talk to Guillermo Altares
Janne Teller talks to Marian Hens
Jordi Soler talks to Juan Cruz