Catalonia votes on independence - in pictures

Security forces used batons and fired rubber bullets in an attempt to disperse the crowds. Many were injured. "We were forced to do what we did not wish to do," said Spanish government delegate to Catalonia, Enric Millo. "Puigdemont and his team are solely responsible" for the violence, he added.

Supporters of an independent Catalonia have long accused the central government of denying the will of the people. At this Barcelona rally ahead of the Sunday vote, one of the protesters holds up a picture of late Spanish dictator Francisco Franco kissing the current Prime Minister Mariano Rajoy.

Anti-independence protesters also took to the streets of Barcelona to show their support for a united Spain. In this photo from Saturday, one of them is shouting at a member of the Catalan regional police force, called Mosso d'Esquadra.

Ahead of the referendum, activists distributed voting material and paraphernalia despite the government ban. The Catalan authorities in Barcelona said that the vote would be legally binding.

Rajoy's government has rejected the independence referendum as unconstitutional and pledged to shut down voting. Many opponents of Catalan separatism gathered in Madrid on Sunday, chanting "Viva Espana" and "Catalonia is Spain."

Spanish authorities deployed thousands of extra police to the region. They received orders to prevent voting and seize ballot boxes. Security forces patrolled the polling stations in the early hours of Sunday morning.

Activists decided to camp out at the polling stations in case police tried to shut the venues down.

Reports of violence started coming in early on Sunday. Scuffles broke out near the city of Girona, where Catalan regional leader Carles Puigdemont was due to cast his ballot. The police raided the polling station, forcing Puigdemont to vote at a different location.

Pro-independence protesters tried to prevent the police from confiscating ballots and ballot boxes. Catalan officials say that, despite Madrid's efforts, 73 percent of about 6,000 polling stations were open on Sunday.

Pro-independence activists were instructed to "practice passive resistance" while attempting to delay the security forces from disrupting the vote. The movement supplied their protesters with red carnations to give to the officers. However, police reported they were also pelted with stones.

On Sunday morning, Catalan officials said people could also use ballots they printed at home, and vote at any open polling station if their designated booth was closed.

While a June poll indicated that a majority of Catalans would be in favor of remaining within Spain, it also showed that independence supporters were far more likely to vote on a referendum. Madrid's crackdown is sure to fan the flames of the independence movement.