NEW YORK — Stocks plunged again Wednesday as investors turned their attention back to the weak global economy and Europe’s debt problems. Most of the big gains that followed a Federal Reserve pledge to extend super-low interest rates vanished.

The Dow Jones industrial average fell 345 points, or 3 percent, to 10,895 in early afternoon trading. The average plummeted more than 300 points within minutes of the opening bell and was down as many as 456 points by late morning.

On Tuesday, the Dow gained 429 points after the Fed said it planned to keep interest rates extremely low at least through the middle of 2013. It was the first time the Fed announced such a timetable.

But by Wednesday, investors were focused on the pessimistic side of the Fed’s announcement: The central bank expects the economy to stay weak for at least two more years.

“Investors are still trying to discern whether it’s going to be a double-dip recession or just a slowdown,” said Oliver Pursche, president of Gary Goldberg Financial Services.

The Standard & Poor’s 500 fell 32 points, or 2.8 percent, to 1,140. The Nasdaq fell 61, or 2.5 percent, to 2,421.

Gold set yet another record price as money poured into investments considered safe at an extremely volatile time for the financial markets. Gold rose $44 per ounce to $1,787 and briefly rose to $1,800 per ounce.

The 10-year Treasury note, which has also served as a haven, also rose sharply. Its yield fell to 2.16 percent from 2.26 percent late Tuesday. It had reached a record low of 2.03 percent on Tuesday. A bond’s yield falls when its price rises.

Investors have bought U.S. government debt even after S&P stripped the United States of its top credit rating, AAA, late last week.

On top of concerns about the U.S. economy, attention is still on Europe, where investors worry that Italy and Spain may be the next countries unable to repay their debts.

French President Nicolas Sarkozy cut short his vacation for emergency meetings with government minsters amid concerns that France could become the next AAA-rated country downgraded. The French CAC 40 stock index fell 5.5 percent. Societe Generale, France’s second largest bank, was down more than 20 percent at one point.

The European financial system has been battered by fears about banks’ holdings of bonds issued by heavily-indebted countries, such as Greece and Portugal. This week, those concerns have evolved into fears about banks’ exposure to other banks, analysts say.

“It’s the same game of Old Maid playing out in Europe that was played out here during the subprime mortgage crisis,” said Quincy Krosby, an economist and market strategist with Prudential financial. As the contagion hits ever-larger countries, such as France, “the ramifications for the banks are more detrimental,” Krosby said.

In Asia, the concern is that higher inflation in China could lead to slower growth. Auto sales in China rose just 6.7 percent in July, on pace for a yearly slowdown from 2010 sales growth of 32 percent.

China, Brazil and other less-developed countries have provided the strongest economic growth since the world began to recover from recession in 2009.

Only 19 stocks in the S&P 500 index rose early Wednesday.

Financial stocks led the U.S. market lower. Bank of New York Mellon Corp. fell 6.8 percent after it said it will cut 1,500 jobs, or about 3 percent of its global work force, to lower costs. As a group, financial stocks in the S&P 500 fell 5.4 percent, the biggest decline of the 10 industries that make up the index.

One big reason: investors don’t know how exposed U.S. banks are to the European financial system, via their ownership of debt of European countries and banks, Krosby said. From a trader’s perspective, “at the end of the day, if there’s one cockroach, there’s a million,” she said.

On Tuesday, the Dow swung 600 points in the final 90 minutes of trading, from a 205-point decline to the 429 point gain, after the Fed announcement, which also said the central bank was considering “policy tools” to help the economy. It was the Dow’s 10th-best point gain.

As recently as June, the Fed had said that the slowing recovery was due to temporary factors, such as high gasoline prices and the disruption to manufacturers following Japan’s March earthquake.

But on Tuesday, the central bank acknowledged those factors were only part of the reason that the economy grew at its slowest pace in the first half of this year since the recession ended in June 2009.

The statement “was essentially a full admission that the Fed had not fully gotten their arms around the permanence to the weak trends in the economy,” William O’Donnell, head of U.S. Treasury strategy at RBS Securities, wrote in a report.

Economists have become more pessimistic about the U.S. recovery in the last month. Manufacturing is barely growing, people are spending less, and the job market isn’t expanding fast enough to bring down unemployment.

Concerns about the global economy have overshadowed strong corporate earnings. On Wednesday, the parent of Macy’s and Bloomingdale’s said profits were 64 percent higher than a year ago because of strong sales. Quarterly profit was up 52 percent at Polo Ralph Lauren Corp.

Cree Inc., a maker of products used in light-emitting diodes, or LEDs, rose 14.9 percent after it reported earnings late Tuesday that were better than analysts expected.

And the Walt Disney Co. said late Tuesday that profit rose 11 percent last quarter. Stronger revenue from its ESPN sports television network and theme parks made up for lackluster box-office results. Its stock fell 9.6 percent.