LONDON // Authorities arrested 90 people after racially charged violence erupted between a group protesting Islamic extremism and counter-demonstrators in the central English city of Birmingham, police said today. The clashes erupted yesterday when a rally by the English Defence League ran into counter-demonstrators including anti-fascists and youths of South Asian descent, West Midlands Police said. About 200 people were involved in the clashes in downtown Birmingham, police said. Television footage showed masked or hooded youths throwing projectiles and running from riot police through the diverse city's downtown area. Police said the 90 people detained - all males aged 16 to 39 - and were arrested on suspicion of criminal damage and violent disorder. It was not immediately clear how many were protesters and how many were counter-demonstrators. Clashes also erupted last month at a similar demonstration in Birmingham, a diverse city of about a million people where nearly a third of the population is non-white. The English Defence League blames counter-demonstrators for inciting violence at its rallies. It has planned protest marches in other cities, including one next month in Manchester.