NEW YORK — Financial markets extended their declines Tuesday as investors worried that lawmakers were beginning to doubt the necessity of a broad government bailout for financial institutions as a way to revive ailing credit markets.

Top economic officials updating Congress about efforts to work out a $700 billion financial rescue plan faced a greater degree of second-guessing from lawmakers than some investors had expected. The Dow Jones industrials, which had been higher for the first half of the session ended at the lows of the day, tacking a 161-point loss onto a steep drop from Monday.

Still, trading appeared more orderly than Monday, when investors rushed into hard assets like oil and gold. Meanwhile, demand remained high for 3-month Treasury bills, considered the safest short-term financial asset, while the dollar regained some ground after being hard hit Monday.

The dollar, whose decline Monday drove some of the frenetic trading in other markets, regained some of its lost ground against the euro, while gold prices declined after starting the week with a big advance.

The Dow fell 161.52, or 1.47 percent, to 10,854.17 after having risen more than 125 points in the early going and then falling by more than 180. With Monday’s 370-point decline, the blue chips are down 534 points, or 4.69 percent, for the week.

Broader stock indicators also fell Tuesday. The Standard & Poor’s 500 index fell 18.87, or 1.56 percent, to 1,188.22, and the Nasdaq composite index fell 25.65, or 1.18 percent, to 2,153.33.

Light, sweet crude for November delivery fell $2.76 to settle at $106.61 on the New York Mercantile Exchange. The October contract, which expired Monday, surged as much as $25.45 to $130 before falling back to settle at $120.92, an advance of $16.37.