Stocks Drop; Dow Down More Than 300

Weak reports on manufacturing and construction spending

Stocks were down sharply in early afternoon trading as Wall Street struggles to shake off the first down January for the Dow Jones industrial average and the Standard & Poor's 500 since 2010.

Weaker reports on U.S. manufacturing and construction spending brought fresh concerns about the economy.

Investors were also disappointed in auto sales from General Motors and Ford.