Security fears weighed on stocks last week as investors remained skittish pending a resolution to events unfolding in Pakistan, where military forces circled Al Qaeda holdouts. The Dow Jones industrial average closed down 0.5 percent to end the week at 10,187. On Friday, blue chips such as United Technologies Corp.—the day’s biggest loser, closing down 2.3 percent—were in the dumps. GE, Citigroup and IBM, among others, all saw declines on Friday. Shares in sportswear manufacturer Nike, trading on the New York Stock Exchange, were up 0.2 percent on an earnings report showing 21 percent revenue growth from the past quarter. On the Big Board, Omnicom shares were up 1.8 percent to close the week at $77.61, while IPG slid 3.6 percent to $15.13. WPP, trading as American Depository Receipts on the Nasdaq, rose 0.5 percent to close at $51.55.