NEW YORK, Aug. 31 (Xinhua) -- U.S. stocks declined on Monday after global equity market was gripped by a sell-off. Financial and energy stocks led the market lower.

    Stocks throughout the world retreating on speculation the six-month rally has outpaced prospects for earnings growth also weighed on the market. China's main index plunged 6.7 percent. Japan's Nikkei stock average fell 0.4 percent. European markets were also lower.

    In New York, financials were among the worst performers. Morgan Stanley plunged after being downgraded to "neutral" from "buy" at Bank of America/Merrill Lynch on valuation.

    Shares of America International Group were down sharply on Monday following an analysis over the weekend by Barron's, which said the stock is overpriced.

    Meanwhile, commodity stocks tumbled as copper plunged the most in two months and crude oil fell below 70 U.S. dollars a barrel.

    In corporate news, oilfield services company Baker Hughes Inc. said it will buy BJ Services Co. for 5.5 billion U.S. dollars in a cash-and-stock deal.

    And Disney agreed to purchase Marvel Entertainment for about four billion dollars. Marvel's shares surged on the news.

    The Dow Jones fell 47.92 to 9,496.28. Broader indexes also went lower. The Standard & Poor's 500 index dipped 8.31 to 1,020.62, and the Nasdaq fell 19.71 to 2,009.06.