Spanish riot police have violently clashed with people who had gathered for a banned referendum on the region's independence from Spain, injuring nearly 850 people.
According to the regional government, some 844 people have been injured in disturbances across Catalonia on Sunday.
Shocking images and videos of police repression have been shared across social media platforms with users condemning the excessive use of force.
The hashtag #NoEnMiNombre, or Not In My Name, has been used to denounce the violence.
"Moment the National Police broke the fingers of Marta Torrejillas."
The president of Catalan, Carles Puigdemont, has also condemned the violence.
"Today, the Spanish state has written a shameful page in its history with Catalonia," he said at a press conference.
In Madrid, people have gathered in the Plaza del Sol to show their solidarity with the people of Catalan.
"The actions of the police have been totally disproportionate. They explicitly violate the fundamental right to meet freely, to protest, to free speech, free association and political participation," Delkader told teleSUR.
"The Spanish government has only offered a violent and judicial response to what is a political problem," he added.
"Lots of people gather in the Plaza de Sol screaming loud and clear that Catalonia is not alone."
Repleta la Puerta del Sol en Madrid contra la represión de Rajoy, que erró grueso en su intento de aislar a Cataluña el día del referéndum pic.twitter.com/YFnFhqLE2p— Juan Manuel Karg (@jmkarg) October 1, 2017
"The Plaza de Sol in Madrid is filled with people against Rajoy's repression, who made a grave error in trying to isolate Catalonia on its referendum day."
As Spanish police wielded batons and fired rubber bullets at crowds attempting to vote in Catalonia's banned independence referendum, the region's own police force gave many voters a much gentler reception.
In Catalonia's pro-independence heartland, among the farming towns of Osona county north of Barcelona, the Catalan force made little attempt to remove people from polling stations despite being tasked with the same court order to shut them down.
Local courts received several complaints on Sunday against the Catalan police accusing them of inactivity and failing to close polling stations, despite the court order, the region's High Court said in a statement.
Firemen in Catalonia also formed a human shield to protect protesters from the riot police.
Firemen in Catalonia having to protect people from police violence. Surely the police should protect people from violence not perpetrate it. pic.twitter.com/AlMCQlZ5i2— Alison ن (@alijaneparti) October 1, 2017
Leaders from across the world have criticized the heavy-handed response to the referendum.
U.K. labor leader Jeremy Corbyn called the state violence, "shocking" and urged "the Spanish government must act to end it (violence) now."
Julian Assange also condemned the Spain's violent and repressive streak over its citizens, asking the president of the EU Commission to "suspend Spain from the European Union for its clear violation of Article 2."