(CNN) —
Spain is facing political turmoil this week following a contested independence referendum in the region of Catalonia, which descended into violence and left hundreds injured.
Here’s what you need to know.
More than 2.25 million people turned out to Sunday’s referendum across Catalonia, a region in the northeast of Spain. The regional government said 90% of voters were in favor of a split from Madrid.
But the turnout was low – around 42% of the voter roll. Catalan authorities blamed the figure on the crackdown on the vote initiated by the national government.
Spain’s highest court had ruled the vote illegal under the Spanish constitution. Citing the judicial authority, Madrid flooded Catalonia with thousands of national police in advance of the vote. Officers seized millions of ballot papers and sealed schools and other buildings to be used as polling stations.
On Sunday, the day of the disputed vote, national police launched a concerted effort to prevent people from casting their ballots. Police fired rubber bullets at protesters and voters trying to take part in the referendum, and used batons to beat them back.
FABIO BUCCIARELLI/AFP/Getty Images
People help a man injured by a rubber bullet fired by Spanish police officers outside the Ramon Llull polling station in Barcelona.
Police smashed their way into polling stations, and were seen pulling voters out by the hair and restraining elderly people.
The scenes shocked Catalans and reverberated around Europe.
Almost 900 people were injured, Catalan officials said. Opposition parties criticized Spanish Prime Minister Mariano Rajoy for taking a heavy-handed approach to blocking the vote.
The long-running dispute goes back to the brutal years under Franco, whose dictatorial regime repressed Catalonia’s earlier limited autonomy. In 1979, four years after his death, the region was granted greater autonomy.
In 2006, the Spanish government backed Catalonia’s calls for even greater powers and financial control of the region, granting it “nation” status.
Photos: Divisions in Spain over Catalonia crisis
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Protesters march through Barcelona during a demonstration to support the unity of Spain on October 8. A bitterly contested independence referendum on October 1 has stoked fierce divisions in the northeastern region of Catalonia and across Spain.
Photos: Divisions in Spain over Catalonia crisis
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Riccardo Dodich
Thousands of people gather in Barcelona to rally for unity in Spain on October 8.
Photos: Divisions in Spain over Catalonia crisis
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Protesters hold Spanish flags during a demonstration against independence for Catalonia on October 8.
Photos: Divisions in Spain over Catalonia crisis
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Demonstrators urge a peaceful dialogue to resolve the crisis over Catalan independence on Saturday, October 7, in Madrid, Spain.
Photos: Divisions in Spain over Catalonia crisis
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Emilio Morenatti/AP
Crowds raise their hands during a demonstration October 7 in Barcelona encouraging talks to ease tensions over independence. Catalan nationalists argue the region is a separate nation with its own history, culture and language. But many Catalans also oppose separatism from Spain.
Photos: Divisions in Spain over Catalonia crisis
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People show their hands painted in white during a demonstration urging dialogue on October 7 in Madrid. Neither the Catalan regional government nor the national government in Madrid has been willing to give ground since the referendum.
Photos: Divisions in Spain over Catalonia crisis
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A woman wears a sticker with the Spanish word for "peace" at a demonstration in Madrid on October 7.
Photos: Divisions in Spain over Catalonia crisis
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Protesters with Spanish flags gather to demonstrate against independence for Catalonia in Madrid on October 7.
Photos: Divisions in Spain over Catalonia crisis
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People attend a protest in Barcelona on Monday, October 2, a day after hundreds were injured in a police crackdown during the banned referendum. The Catalan government claimed victory after pushing forward with the vote despite Spain's Constitutional Court declaring it illegal.
Photos: Divisions in Spain over Catalonia crisis
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Manu Fernandez/AP
Catalan President Carles Puigdemont greets regional government workers before a meeting at the Palace of the Generalitat in Barcelona on October 2.
Photos: Divisions in Spain over Catalonia crisis
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Independence supporters gather in Barcelona after Catalonia's separatist government held a referendum to decide if the region should split from Spain on Sunday, October 1.
Photos: Divisions in Spain over Catalonia crisis
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A member of the Catalan National Assembly cries at the end of the voting day on October 1.
Photos: Divisions in Spain over Catalonia crisis
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Felipe Dana/AP
Spanish riot police remove fences thrown at them as they try to prevent people from voting in Barcelona, Spain, on Sunday, October 1.
Photos: Divisions in Spain over Catalonia crisis
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Pro-referendum supporters clash with members of the Spanish National Police after police tried to enter a polling station to retrieve ballot boxes.
Photos: Divisions in Spain over Catalonia crisis
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Pro-referendum supporters lock a gate to a polling station as members of the Spanish National Police arrive to control the area during voting at the Escola Industrial of Barcelona.
Photos: Divisions in Spain over Catalonia crisis
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Manu Fernandez/AP
Spanish National Police clash with pro-referendum supporters in Barcelona.
Photos: Divisions in Spain over Catalonia crisis
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Alvaro Barrientos/AP
Pro-independence supporters cover a mock ballot box with Estelada Catalan flags in Pamplona, northern Spain.
Photos: Divisions in Spain over Catalonia crisis
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Manu Fernandez/AP
Spanish National Police clash with pro-referendum supporters in Barcelona.
Photos: Divisions in Spain over Catalonia crisis
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People play games in a square where a giant pro-independence Estelada Catalan flag is displayed.
Photos: Divisions in Spain over Catalonia crisis
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Bob Edme/AP
A woman celebrates after voting at a polling station in Barcelona on October 1.
Photos: Divisions in Spain over Catalonia crisis
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People help a man injured by a rubber bullet fired by Spanish police officers outside the Ramon Llull polling station in Barcelona.
Photos: Divisions in Spain over Catalonia crisis
PHOTO:
Emilio Morenatti/AP
Pro-referendum supporters embrace as Spanish National Police try to remove them from the Ramon Llull school in Barcelona.
Photos: Divisions in Spain over Catalonia crisis
PHOTO:
Santi Palacios/AP
People queue to vote at a school in Barcelona.