Spain's protest-hit northeast was gripped by a general strike Friday as thousands of "freedom marchers" converged on Barcelona for a mass show of dissent over the jailing of nine Catalan separatist leaders.
With the angry demonstrations entering their fifth day, activists blocked a string of roads in the wealthy northeastern region, cutting off the main cross-border highway with France.
Workers were also downing tools against Monday's Supreme Court verdict in which the separatist leaders were handed long jail terms over a banned referendum and an abortive independence declaration two years ago.
As well as the strike, tens of thousands of people streamed into Barcelona after a three-day march from five Catalan towns in a bid to cause chaos on the roads in a region that accounts for about a fifth of Spain's economic output.
They were due to gather for yet another massive demonstration -- expected to be the largest yet.
By early afternoon, thousands of striking students were marching through the city, waving signs reading: "We the people will not yield" and "Free the political prisoners".
"We have to push a bit more and we'll get what we want," said 18-year-old Miquel Flores, a nursing student, referring to a referendum on independence.
"The strength of the Catalan people is unstoppable."
The huge turnout came after yet another night of violent clashes, which Catalan regional interior minister Miquel Buch said involved "fewer incidents, but more violent".
"The criminal and violent behaviour we've seen in Barcelona is intolerable," he said, insisting such unrest had "nothing to do with the separatist claim".
And Barcelona city council said the first three days of clashes had cost an estimated 1,575,000 euros ($1,755,000) in damage, without taking into account Thursday's vandalism.
So far, more than 700 large wheelie bins have been torched, while mob violence had also damaged traffic lights, street signs, trees and the city's bike-share service, it said.
La Boqueria market shuttered
At Barcelona's El Prat airport, 55 flights were cancelled, and Spanish carmaker SEAT halted production at its Martorell assembly plant which employs some 6,500 people, in anticipation of transportation problems.
In Barcelona, Spain's top tourist destination, the Sagrada Familia basilica closed due to protesters blocking access, and the famous Liceu opera house cancelled Friday night's performance.
Barcelona's huge wholesale market, which exports around a third of the region's fresh produce, was barely trading on Friday, and at the city's famed La Boqueria market, most of the stalls were closed.
At one stall, Barcelona-born Susana Medialdea, 53, was selling olives and pickles entirely dressed in yellow.
"I came in voluntarily to work but only as long as I could wear yellow to express my total disagreement with the sentence," she told AFP, saying she felt "very angry" about it.
But another veteran stallholder took the opposite view.
"I am real Catalan but I don't support this independence project at all, people are letting themselves be used, above all the youth," said 75-year-old Carmen Isern, accusing the secessionists of dishonesty.
"We've had seven years of lies. They only tell the teenagers bad things about Spain."
Real Madrid - Barca clash postponed
Across the region, many roads were blocked off either by demonstrators, or by burning tyres or mattresses, and in one case, activists threw nails on the ground, puncturing tyres on passing cars.
With the region mired in chaos, football authorities cancelled the Barcelona and Real Madrid Clasico set for October 26 at the Nou Camp stadium. Both clubs had reportedly refused an offer to hold the match in Madrid.
The general strike follows a fourth night of unrest, after hundreds of protesters rampaged through Barcelona, torching improvised roadblocks and tossing Molotov cocktails at police, AFP correspondents said.
Emergency services said 42 people were injured across the region overnight, while police said they had arrested around 110 people since Monday, at least 11 overnight.
Berta Barbet, a political scientist at the University of Barcelona, told AFP on Thursday the demonstrations "in their current size" would likely only last a week.
The Supreme Court's explosive decision has thrust the Catalan dispute to the heart of the political debate as Spain heads towards a fourth election in as many years, which will be held on November 10.
Workers were also downing tools against Monday's Supreme Court verdict in which the separatist leaders were handed long jail terms over a banned referendum and an abortive independence declaration two years ago