Global Markets Reel

Global stocks tumbled again Monday as the U.S. credit-rating downgrade by S&P sent jitters through markets. The worries outweighed relief that the European Central Bank pledged to buy up Italian and Spanish bonds to help the two countries avoid defaults. European markets were firmly in the red despite their early momentum, and losses were heavy in Asia. Hong Kong's Hang Seng Index and Japan's Nikkei slid more than 2 percent, and the Shanghai Composite Index lost nearly 4 percent.