Major U.S. and European stock indexes fell between two and three percent in Thursday's trading as nervous investors worried about the European Debt crisis, growing regulation of financial markets, and some downbeat U.S. economic data. The value of the euro also declined.

U.S. economic reports showed slight declines in the job market and future economic growth.  Investors were already concerned about future economic growth after German officials banned a type of financial transaction and called for a tax on financial markets.

The debt crisis behind the market turmoil first came to light in Greece, which is sharply cutting spending.  Officials of the International Monetary Fund say it will take a while for markets to see that the austerity program is credible.  

The austerity program has angered workers, who marched to the parliament in the Greek capital Thursday.  Transportation and other public sector employees went on strike around the country, though many air traffic controllers stayed on the job to avoid hurting the crucial tourism industry.

Some information for this report was provided by AP, AFP, Bloomberg and Reuters.