NEW YORK (AP) - The stock market has had one of its most turbulent days ever. The Dow Jones industrials plunged nearly 1,000 points in half an hour amid concerns that Greece's debt problems could halt the world financial recovery.
The Dow has managed to recover two-thirds of its losses and close down 347 at 10,520. But all the major indexes lost 3 percent in a day that recalled the market turmoil of the 2008 financial crisis.
There were reports that a technical glitch hastened the selling. Even so emotions are running high. Traders are concerned that Greece's economic problems will hurt other European countries and ultimately, the U.S. recovery.
The Standard & Poor's 500 index is off 37 at 1,128. The Nasdaq composite index is off 82 at 2,319.
Only 173 stocks rose on the New York Stock Exchange while 3,002 fell. Volume came to an extremely heavy 2.57 billion shares.
Computer trading intensified the losses as programs designed to sell stocks at a specified level kicked in. Traders use those programs to try to limit their losses when the market is falling. And the selling only led to more selling as prices fell.
"I think the machines just took over. There's not a lot of human interaction," said Charlie Smith, chief investment officer at Fort Pitt Capital Group. "We've known that automated trading can run away from you, and I think that's what we saw happen today."
Still, emotions were running high. Down 998.50 points in mid-afternoon, the Dow recovered to a loss of 505. Meanwhile, interest rates on Treasurys soared as traders sought the safety of U.S. government debt. The yield on the benchmark 10-year note, which moves oppoosite its price, fell to 3.37 percent from late Wednesday's 3.54 percent.
"The market is now realizing that Greece is going to go through a depression over the next couple of years," said Peter Boockvar, equity strategist at Miller Tabak. "Europe is a major trading partner of ours, and this threatens the entire global growth story."
The stock market has had periodic bouts of anxiety about the European economies during the past few months. They have intensified over the past week even as Greece appeared to be moving closer to getting a bailout package from some of its neighbors.
The losses in stocks were so widespread that just 139 stocks rose on the New York Stock Exchange, compared to 3,029 that fell. The major indexes were all down more than 4 percent.