Spaniards suffered rush-hour travel chaos and pickets gathered outside factories as unions launched a 24-hour general strike Wednesday to protest tough government labour reforms and austerity measures.
In Madrid, frustrated commuters walked to work or waited at bus stops or at metro stations, garbage was left uncollected and thousands of union leaflets urging workers to stay at home littered the streets.
Newspaper kiosks were devoid of papers as the country's main dailies went on strike on Tuesday, a day early.
What the unions described as "information pickets" were positioned outside factories.
There was no immediate information on the overall level of participation.
Spain's two main unions, the CCOO and the UGT, said almost 100 percent of workers in the steel industry stayed off work, while reporting an "almost complete" stoppage in the car-making sector.
The protest had been expected to draw a weak response, as the socialist government's labour reforms and belt-tightening measures are widely viewed as inevitable.
A poll published Friday in the newspaper Publico said some 55 percent of Spaniards thought the strike was justified, but only 18 percent planned to take part; and 71 percent believed it would not force the government of Prime Minister Jose Luis Rodriguez Zapatero to change course.
The unions called the strike to protest a sweeping overhaul of the country's rigid labour market.
Unions are also fighting steep spending cuts, including an average state employee salary reduction of five percent, a pensions freeze and plans to gradually raise the retirement age to 67 from 65.
It is the country's first general strike since 2002 and the first since Zapatero took office in 2004.
Unions last week struck an unprecedented deal with the government to ensure minimum services.
The deal provides for a minimum of 20-40 percent of international flights and 10 percent within the Spanish peninsula.
It will allow 20 percent of high speed trains and 25 percent of district trains, including 30 percent for morning rush hour. But no regional or long-distance trains are guaranteed.
The unions have also called about 100 street demonstrations across the country. In the capital Madrid, a march is scheduled for Wednesday evening across the city centre.