Defying a ban by Madrid election officials, several thousand people gathered in Puerta del Sol on Wednesday as mass demonstrations against unemployment and the government's social policies swelled across the country for the fourth day.

Anti-riot police were called in to enforce the ban, but at press time no one had been dislodged from Madrid's main square. People appeared in good spirits despite initial fears of confrontations.

Earlier in the day, the Madrid Electoral Board banned organizers of the so-called 15-M movement from holding its rally. The board ruled that there existed "no special or serious reasons" for the urgent call for the mass demonstration. The Real Democracy Now platform, which is spearheading the movement, called on demonstrators to camp out in Madrid's Sol and other main squares in cities across Spain until Sunday's elections. But Madrid Board members decided that the protests "can affect the election race and the freedom of citizens to cast ballots" for whom they choose. The Central Electoral Board, which decides campaign policy for the entire nation, said it would make a final ruling in lieu of the different decisions being adopted by regional officials.

Saying they are fed up with high unemployment and a faltering economy, demonstrators, mostly youths, are demanding a voting boycott against the major political parties in Sunday's local and regional elections.

The nationwide protests, which appeared to be drumming up more support on Wednesday, have become a surprise element in the race. "We are here to stay," said one protester in Seville's main plaza. The parties have taken up sides for and against the demonstrators but on Wednesday some officials begin paying more attention to the demands from the movement.

"Without a doubt when they tell us that we need to learn a new language to communicate better, we need to reflect on this critique," said Madrid Mayor Alberto Ruiz-Gallardón of the Popular Party in A Coruña.

Tomás Gómez, the Socialist candidate for the job of Madrid regional premier, said that he didn't agree with the electoral board's decision. "I don't see anything wrong in letting them continue expressing their outrage and discontent," he said.

The United Left (IU) party, which first came out in support of the movement, accused both the PP and the Socialists of being behind the ban. "We demand that [both parties] show their faces, assume their responsibilities and stop hiding behind the Electoral Board," said IU committee member Amanda Meyer.

For his part, IU Deputy Gaspar Llamazares called the board ruling "a disastrous decision" and feared it would lead to more violence across the country.

After the board issued its ruling, more people began gathering in Puerta del Sol while anti-riot police cordoned off the area. Social networks, such as Twitter and Facebook, helped mobilize the demonstrators. Police were demanding to see the ID cards of protesters "in case we have to arrest them," as one officer put it.

A student from Venezuela told EL PAÍS: "I am here today in Sol because in Caracas we tried similar student protests against Chávez. These things can serve for something."