Demonstrators call themselves "los indignados" (the indignant), the movement which spawned similar protests worldwide, has called for 96 hours of continuous protest over government austerity measures, banks, politicians, economic recession, and the highest unemployment in the eurozone. (Andrea Comas/Reuters)

Thousands of Spaniards angered by their grim economic prospects and political handling of the international financial crisis turned out for street demonstrations in the country's cities, marking the one-year anniversary of a movement that inspired similar pressure groups in other countries.

Protesters in Madrid converged on the central Puerta del Sol plaza Saturday evening and aimed to stay for three days. But authorities warned they wouldn't allow anyone to camp out overnight, and up to 2,000 riot police were expected to be on duty.

Marches were also held in Barcelona, Bilbao, Malaga and Seville. Sympathizers held demonstrations in other European cities.

The protests began May 15 last year and drew hundreds of thousands of people calling themselves the Indignant Movement. The demonstrations spread across Spain and Europe as anti-austerity sentiment grew.

Spain is in deep economic difficulty, prompting fears it may need a bailout similar to those helping Greece, Ireland and Portugal. It is in recession, and unemployment stands at almost 25 percent — the highest among the 17 countries using the euro. One in two Spaniards under the age of 25 are out of work.

Prime Minister Mariano Rajoy's conservative government has enacted deep spending cuts to reduce the national debt, but many people blame those measures for deepening families' financial plight.

A year ago, the "indignados" pitched tents and occupied town and city squares across Spain for weeks. Demonstrators clashed with police who eventually moved in to evict them.

"We are here today to celebrate one year since the ... movement started and though we have achieved some things the situation is much worse now, so we need to keep fighting to get things better and that's why we are here today," said 40-year-old activist Ana Pancorvo, who was hooking up with one of four Madrid marches due to converge on the Puerta del Sol.

Antonio Barroso, a London-based Europe analyst for Eurasia Group, said he doubted the Spanish protests would force Rajoy's government to change its policies.

The demonstrations "will probably have no impact on the government's strategy," he said in a written analysis.

Protests also took place Saturday in other European cities, and were planned in South American countries including Brazil and Chile.In Britain, several hundred anti-capitalist protesters from the Occupy movement marched peacefully through London's financial district, rallying outside the offices of major banking groups such as Merrill Lynch and Santander.

Hundreds also took to the streets in Brussels and Lisbon, Portugal, where the turnout was lower than last year.

The protesters called for governments to enact a host of measures, including a global tax on financial transactions and more democratic international financial bodies