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FILE - In this May 11, 2007, file photo, a Wall Street sign is mounted near the flag-draped facade of the New York Stock Exchange. World stock markets sank on Friday, Aug. 1, 2014 with European benchmarks opening sharply lower after Wall Street's sharp sell-off. Asian stock markets posted modest losses as strong reports on China's economy countered some of the pessimism. (AP Photo/Richard Drew, File)

NEW YORK (AP) — U.S. markets are moving lower, extending a major sell-off from the day before.

Energy stocks fell the most after Chevron reported weaker oil and gas production. Exxon Mobil had reported disappointing production figures the day before.

The Dow Jones industrial average lost 110 points, or 0.7 percent, to 16,454 as of noon Eastern time. The blue-chip index lost 317 points the day before, its biggest one-day drop since February.

The Standard & Poor's 500 index fell 12 points, or 0.7 percent, to 1,918 and the Nasdaq composite fell 39 points, or 0.9 percent, to 4,329.

The S&P 500 index is down 3 percent for the week and is heading for its worst week of the year.

Bond prices rose. The yield on the 10-year Treasury note fell to 2.49 percent.