A huge crowd with Catalan flags has paralyzed central Barcelona as people from all across the region protested the harsh prison sentences for pro-independence leaders by the Spanish court and called for parting ways with Madrid.

The police estimated that at least 525,000 turned up in the center of Barcelona, local media cited law enforcement. “Independence,”“The streets will be ours” and “Freedom to political prisoners” were among the chants heard at the massive gathering.

The rally continued more or less peacefully for a few hours, but was eventually marred by more serious violence as some of the protesters started building barricades and setting garbage containers on fire.

They tossed stones and other foreign objects at the riot police, who were seen firing back – presumably using rubber bullets or other projectiles – and charging at the rioters with batons.

Some of those, involved in clashes with police, were said to be right-wing thugs, who actually oppose the Catalan independence. The footage from the scene showed people carrying Spanish national flags and giving Nazi salutes.

WARNING: DISTURBING IMAGES

Spanish ultranationalists clash with Antifa activists in #Barcelona amid protests for Catalan Independence pic.twitter.com/piXlxdse8J — RT (@RT_com) October 18, 2019

As night fell, some of the sites of the clashes resembled a war zone, with burning barricades, rubble everywhere and clouds of thick white smoke in the air.

Violent episodes may attract media attention, but they’re just a small part of the picture, Toni Casserras from the Catalan ‘Free People’ party told RT. The majority of the pro-independence activists believe in peaceful civil disobedience and they will keep going out into the streets.

“The protests [in Catalonia] are being sustained for several years and – despite the violence, which is applied to the protesters; despite imprisoning our leaders – people don’t give up. Protests are efficient, especially, massive protests.”

The general strike kicked off in Catalonia’s capital early on Friday, with small businesses not opening and employees of bigger firms and factories skipping work. The walkout caused the cancellation of almost 60 flights at Barcelona-El Prat Airport as well as the disruption of train operations in some parts of the region. Many more flights were canceled in Barcelona in previous days as the demonstrators made the airport completely inaccessible.

Road traffic was also affected as the protesters blocked roads and highways by setting tires on fire and leaving nails on the asphalt.

The AP-7 highway was cut off near the French border, paralyzing the crossing between Spain and France. In Girona, farmers drove their tractors across the central streets to the cheers of crowds to show Madrid that they mean business.

The large groups of people who marched from various parts of Catalonia started arriving in Barcelona at around noon Friday and brought the city to a standstill. They had set out on their journey to the regional capital from Girona, Tarragona, Vic, Martorell and others cities by foot on Wednesday.

Students staged minor protests throughout Barcelona in anticipation of the major rally, which started at around 5pm local time. A group of pro-independence activists also camped outside the entrance to the iconic Sagrada Familia basilica in the heart of Barcelona, preventing tourists from coming in.

READ MORE: Barcelona’s Sagrada Familia cathedral shut down by Catalan ‘Picnic for the Republic’ protesters (PHOTOS, VIDEO)

Barcelona has been in turmoil since Monday when Spain’s Supreme Court sentenced nine politicians and activists to up to 13 years behind bars for organizing the referendum on Catalonia’s independence in 2017. The plebiscite, which saw the majority of the population voting for secession from Spain, was labeled illegal by Madrid and met with a harsh police crackdown that left hundreds of people injured.

As for the latest protests, Thursday was the most violent day of the rallies in Barcelona as the demonstrators built barricades, burnt bonfires and clashed with police. Dozens were hurt on both sides.

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