Wall St stumbles on fresh risk aversion

NEW YORK (Reuters) - Stocks fell on Friday as investors lost their appetite for risk and sold shares of financials, home builders and other sectors that have been at the center of the credit market crisis.

American Express Co (AXP.N: Quote, Profile, Research, Stock Buzz) shares led declines on the Dow, while Bank of America Corp (BAC.N: Quote, Profile, Research, Stock Buzz) was the biggest drag on the S&P 500. The S&P Financials were the worst performer of the 10 major industry groups, losing 2.9 percent.

In a sign of nervousness in the market, the U.S. investment-grade credit derivative index widened to a record. Analysts said U.S. credit protection costs were surging on rumors that some structured credit vehicles with heavy losses are being liquidated.

Amid the uncertainty, investors will be more inclined to sell on a Friday, traders said.

"People are wary of taking risk going into the weekend. There's selling in some of the large banks and some of the consumer finance names," said Justin Wiggs, trader at Stifel Nicolaus Capital Markets in Baltimore.

The Dow Jones industrial average .DJI was down 102.75 points, or 0.84 percent, at 12,144.25. The Standard & Poor's 500 Index .SPX was down 10.40 points, or 0.78 percent, at 1,326.51. The Nasdaq Composite Index .IXIC was down 2.60 points, or 0.11 percent, at 2,290.43.

Trading has been jittery in the past few days, with indexes flipping direction several times during the session.

"A lot of people don't want to take a stand at this point, there's a lot of passive order flow, not big bets being taken," Wiggs said.

American Express shares were down 5 percent at $44.15 and Bank of America stock was down 2.8 percent at $42.17.