NEW YORK – The stock market had one of its most turbulent days in history as the Dow Jones industrials fell to a loss of almost 1,000 points in less than half an hour on fears that Greece's debt problems could halt the global economic recovery.

The market's plunge came less than 90 minutes before the end of trading. The Dow's drop was its largest loss ever during the course of a trading day, but it recovered to a loss of 347 at the close. All the major indexes lost more than 3 percent.

There were reports that the sudden drop was caused by a trader who mistyped an order to sell a large block of stock. The drop in that stock's price was enough to trigger "sell" orders across the market.

Still, the Dow was already down more than 200 points as traders watched protests in the streets of Athens on TV. Protestors raged against austerity measures passed by the Greek parliament. But traders were not comforted by the fact that Greece seemed to be working towards a resolution of its debt problems. Instead, they focused on the possibility that other European countries would also run into trouble, and that the damage to their economies could spread to the U.S.

The Dow fell 998.50 points in its largest point drop ever, eclipsing the 780.87 it lost during the course of trading on Oct. 15, 2008, during the height of the financial crisis. The Dow closed that day down 733.08, the biggest closing loss it has ever suffered.