Catalan referendum: Clashes as voters defy Madrid

Catalonia's independence referendum has begun in chaotic fashion, with clashes occurring as police attempt to prevent the vote from taking place.

The Spanish government has pledged to stop a poll that was declared illegal by the country's constitutional court.

Police officers are preventing people from voting, and seizing ballot papers and boxes at polling stations.

In the regional capital Barcelona, witnesses said police had fired rubber bullets during pro-referendum protests.