Spanish police have fired rubber bullets and charged protesters in central Madrid after a huge demonstration against economic crisis measures.
Thick smoke hung in the air early on Friday from plastic bins set alight by protestors chased by police, who hit them with batons when some tried to reach the heavily-guarded parliament at the end of a mostly peaceful march.
AFP reporters at the scene said dozens of protesters lingered, some throwing bottles at police, near the Puerta del Sol, the big square at the heart of the city where a march of hundreds of thousands wound up late Thursday.
A police official said that officers arrested seven people and six others were injured.
Earlier, tens of thousands of public employees, trade union members and other Spaniards have marching in 80 Spanish cities to protest the latest batch of austerity measures approved by the government.
The ruling conservative Popular Party used its majority in parliament to push through the measures on Thursday. They include a rise in sales taxes and a wage cut for civil servants.
Workers yelled in anger branding the crisis measures "robbery".
"Hands up, this is a robbery!" protesters bellowed in Madrid, where a sea of demonstrators crammed the avenues of the city centre.
Unions had earlier called for the more than 80 demonstrations across the country in the latest and biggest in an almost daily series of protests this month.
A sustained string of protests erupted after Prime Minister Mariano Rajoy last week announced the new measures, aiming to save $80bn in order to slash the public deficit.
Smaller protests, organised largely via online social networks, have occurred daily since the latest austerity measures were announced on July 11, with some workers taking to the streets during their morning coffee break.
Hundreds of protesters, including fire-fighters wearing their helmets and police in black T-shirts, have marched through the streets of Madrid, blocking traffic and chanting.
Cristobal Mindoro, Spain's budget minister, defended the measures on Thursday, saying they were needed to lower Spain's borrowing costs.
Under pressure from the European Union to stabilize Spain's public finances, the conservative government also cut unemployment benefits and raised the sales tax, with the upper limit rising from 18 to 21 per cent.
"There is no money in the coffers to pay for public services. We are making reforms that will allow us to better finance ourselves," he said.
Spain had to offer investors sharply higher interest rates on Thursday to raise $3.Ban in debt auctions with maturities of two, five and seven years.
The higher rates suggest investors remain worried over the country's ability to repay its debts as it struggles with its second recession in four years and an unemployment rate of over 24 per cent.
Critics say the government's new austerity measures will worsen economic conditions for ordinary people.
"The new cuts harm the weakest sectors of society without one single measure that involves any effort by companies and the highest earners," the COCO said in a statement.
Unions have called for the protests to be peaceful but clashes broke out on the fringes of some demonstrations in Madrid last week, including one major march by striking coal miners.678
"They have already lowered and frozen our salary and this is the final blow," said Ines Corned, 44, a worker in the justice sector, protesting in Madrid on Tuesday.
"These measures they are taking will not stimulate consumption and will not create jobs," said Corned.
Spain is due this month to become the fourth eurozone country, after Greece, Ireland and Portugal, to get bailout funds in the current crisis when it receives the first loan for its banks.
Eurozone leaders are expected to finalise the deal in a telephone conference on Friday.