NEW YORK - Markets are turning turbulent again after investors were unnerved by more signs of weakness in China, the world's second-largest economy.

U.S. stocks sank 3 percent Tuesday, their third-worst drop this year. The two bigger falls occurred in the last two weeks.

The Dow Jones industrial average dropped 469 points, or 2.8 percent, to 16,058.

The Standard & Poor's 500 index fell 58 points, or 3 percent, to 1,913. The Nasdaq slid 140 points, or 2.9 percent, to 4,636.

Oil prices also fell sharply as traders worried that China's weakening growth would mean lower demand for crude. U.S. oil sank almost 8 percent.

The plunge in oil sent energy stocks sharply lower. Exxon Mobil dropped 4 percent.

Bond prices rose. The yield on the 10-year Treasury note fell to 2.16 percent.