Stocks fell sharply on Wednesday, with the Dow industrials and the S&P 500 briefly down 4 percent on fears over the French banking sector's exposure to shaky European debt and its possible spillover into U.S. banks.

The Dow Jones industrial average lost 426.06 points, or 3.79 percent, to 10,813.71. The Standard & Poor's 500 Index dropped 43.80 points, or 3.74 percent, to 1,128.73. The Nasdaq Composite Index fell 84.49 points, or 3.40 percent, to 2,398.03.