Catalonia's disputed independence referendum rapidly descended into chaos on Sunday as Spanish national police raided polling stations and clashed with voters.
Barcelona's deputy mayor said police fired rubber bullets at people as they attempted to vote in the referendum, which Spain's top court has declared illegal.
Catalan President Carles Puigdemont condemned "indiscriminate aggression" against people attempting to vote peacefully. Regional authorities said 38 people were treated by emergency services by mid-morning.
Spanish National Police prevent people from entering a voting site at a school assigned to be a polling station by the Catalan government in Barcelona.
Spain's national government is implacably opposed to any breakaway moves by the northeastern region. "Police are confiscating ballot boxes to respect the judicial mandate and the law regarding the illegal referendum," Spain's interior ministry said on Twitter Sunday.
In Girona, where Puigdemont was due to vote, police smashed their way into a polling station by breaking a glass window. Puigdemont cast his ballot in a nearby village.
Catalan authorities said Education Minister Clara Ponsati i Obiols was forcibly removed from her polling station.
Regional government spokesperson Jordi Turull told a press conference in Barcelona two hours after polling began that despite the Spanish government's efforts, 73 per cent of the polling stations, 4,661 in total, were open.
He accused Madrid of being responsible for "a state violence unknown to Spain since the age of Franco," referring to the former military dictator Francisco Franco who ruled the country with an iron fist for 36 years until 1975, reports CNN.