Catalonia is a semi-autonomous region in north-east Spain whose history dates back almost a thousand years. The wealthy region has 7.5 million people, with their own language, parliament, flag, anthem, and police force. It also controls some of its own public services. Catalan nationalists have long complained that their region sends too much money to poorer parts of Spain, as taxes are controlled by Madrid. Last October about 90% of Catalan voters backed independence, in a turnout of 43%. Recently Spanish police arrested 9 Catalan independence activists in Barcelona. They face charges of rebellion, terrorism and possession of explosives used in bomb-making. They are associated with the Committees for the Defence of the Republic (CDR), a network of radical groups that advocates direct action to secure independence from Spain. CDR has previously blocked major roads and railway lines. Police believe the activists plan to carry out sabotage and violent attacks on the anniversary of the referendum on independence.