Millions of EU workers have held a day of action against austerity, with protests in Spain and Portugal marred by violence.
General strikes in the two southern countries halted transport and closed businesses and schools, while 21 other states also saw disruption.
Hundreds of flights to and from striking nations were cancelled.
Clashes in Lisbon left nearly 50 people hurt while in Spain at least 70 were injured and some 140 arrests were made.
Wednesday's action was co-ordinated by the European Trade Union Confederation. One of its officials, Judith Kirton-Darling, told the BBC that austerity was not working.
"It's increasing inequalities, it's increasing the social instability in society and it's not resolving the economic crisis," she said.
Unions in Spain and Portugal began their strikes at midnight on Tuesday to protest against austerity measures that have combined tax rises with cuts in salaries, pensions, benefits and social services.
Spain has unemployment of above 25%, the highest rate in Europe.
"They are taking away our future," declared banners hanging in the main squares of Madrid as people massed under the eyes of riot police.
Picketers and police fought at a bus depot in the capital where demonstrators were trying to stop buses from leaving.
Other protesters in Madrid set rubbish bins on fire, filling the central boulevard with smoke, while in Barcelona demonstrators burned police cars.
The government sought to play down the strike, saying the electricity grid registered 80% of its normal usage, but unions said the operations of several large companies, including Danone and Heineken, had ground to a halt.
In neighbouring Portugal, demonstrators took to the streets, carrying banners denouncing the EU, International Monetary Fund (IMF) and European Central Bank (ECB).
The so-called troika has bailed out Portugal to the tune of 78bn euros ($100bn; £62bn), and demanded deep austerity measures in return.
According to figures released on Wednesday, the country's unemployment rate has hit a record 15.8%. Prime Minister Pedro Passos Coelho acknowledged the rise was "bad news" but said it had been expected.
Police charged protesters who had gathered in front of the parliament building in Lisbon, striking them with truncheons as demonstrators hurled stones and rubbish.
In other developments on Wednesday
- Italian cities saw violent clashes between protesters and riot police, who used armoured vehicles to disperse crowds in the capital, Rome, according to Reuters news agency
- Trade unions organised marches in more than 100 cities across France but did not call for a strike
- In Belgium, protesters rallied in Brussels outside the embassies of Germany, Spain, Greece, Cyprus, Portugal and the Republic of Ireland, while a 24-hour rail stoppage severely disrupted the Thalys and Eurostar high-speed rail services
- Hundreds of Greeks gathered outside the parliament in Athens to brandish huge flags of Spain, Greece, Portugal and Italy