Read this: In many parts of the world football evokes great passions and plays an important role in the life of individual fans, local communities, and even nations. R. Kapuscinski says that Europeans who are polite, modest, or humble fall easily into rage when playing or watching football games. The Côte d'Ivoire national football team helped secure a truce to the nation's civil war in 2006 and it helped further reduce tensions between government and rebel forces in 2007 by playing a match in the rebel capital of Bouaké, an occasion that brought both armies together peacefully for the first time. By contrast, football is widely considered to have been the final proximate cause for the Football War in June 1969 between El Salvador and Honduras. The sport also exacerbated tensions at the beginning of the Yugoslav Wars of the 1990s, when a match between Dinamo Zagreb and Red Star Belgrade degenerated into rioting in May 1990.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): What match degenerated into rioting in July 1990?
unanswerable