NEW YORK » The misery worsened on Wall Street yesterday, with stocks piling on the losses late in the session and bringing the two-day decline in the Dow Jones industrials to more than 875 points amid escalating worries about credit markets and financial sector. The Dow lost more than 500 points and all the major indexes slid more than 5 percent.

Steps by the Federal Reserve to reinvigorate the dormant credit markets ultimately weren't enough to calm nervous investors.

Meanwhile, Federal Reserve Chairman Ben Bernanke warned in a speech yesterday that the financial crisis could prolong the difficulty the economy is facing. While his remarks were widely regarded as a sign that an interest rate cut could be in the offing, Wall Street appeared little comforted and focused on his downbeat assessment of the economy.

Earlier, the Fed announced plans to buy massive amounts of corporate debt to jump-start lending in the markets where many companies turn for short-term loans called commercial paper.

But investors remained worried about financial companies like Bank of America Corp., which fell after slashing its dividend and reporting that its third-quarter profit fell 68 percent. The stock fell $8.45, or 26 percent, to $23.77 yesterday. It was by far the steepest decliner among the 30 stocks that comprise the Dow industrials.

And a rumor that Mitsubishi UFJ Financial Group Inc. was pulling out of a deal to acquire up to 24.9 percent of the voting shares of Morgan Stanley sent the investment bank's stock tumbling $5.85, or 25 percent, to $17.65. The companies denied the rumor, but the Street was panicky enough that it still sent Morgan Stanley and other financials tumbling.

Stocks ended lower for the fifth straight session. The Dow fell 508.39, or 5.11 percent, to 9,447.11. The drop came a day after the blue chips fell below 10,000 for the first time in four years. The Dow skidded as much as 800 points on Monday before finishing with a loss of 370.

Broader indexes also fell. The Standard & Poor's 500 index declined 60.66, or 5.74 percent, to 996.23, while the Nasdaq composite index fell 108.08, or 5.80 percent, to 1,754.88.

The dollar was mostly lower against other major currencies, while gold prices rose.

Oil prices rebounded after plunging Monday to an eight-month low on concerns a global recession will undermine demand for crude. Light, sweet crude rose $2.25 to settle at $90.06 a barrel on the New York Mercantile Exchange.

The yield on the three-month Treasury bill, which moves opposite its price, rebounded to 0.76 percent from 0.50 percent late Monday.

The yield on the 10-year note rose to 3.51 percent from 3.50 percent late Monday.

About 2,800 stocks declined on the New York Stock Exchange, while fewer than 400 advanced. Volume came to 1.73 billion shares.

The Russell 2000 index of smaller companies fell 36.96, or 6.20 percent, to 558.95.