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Riskier assets including energy commodities took a hit. Oil prices at one time plunged about eight percent to below 65 dollars a barrel before settling just above 68 dollars. Economic data released in United States offered little comfort to investors.
The Labor Department reported that the number of workers filing new claims for unemployment benefits rose by 25,000 to a seasonally adjusted 471,000 from an upwardly revised 444,000 for the week ending May 15, while analysts were expecting a moderate drop.
Meanwhile, the moving average of new claims over the past four weeks also inched up by 3,000 to 453,500.
The sell off accelerated after the Conference Board said its index of U.S. leading economic indicators, an index meant to gauge the future strength of the U.S. economy, slipped 0.1 percent last month, the first decline in more than a year.
The report added to investors' worries about the global economy. They have been selling heavily the past few weeks amid growing concerns that Europe's debt problems will halt the recovery in the region and hurt the rebound in the U.S.
The Dow Jones industrial average plunged 376.36, or 3.60 percent, to 10,068.01. The Standard & Poor's 500 index tumbled 43. 46, or 3.90 percent, to 1,071.59 and the Nasdaq plummeted 94.36, or 4.11 percent, to 2,204.01.