U.S. stocks closed firmly in the red on Thursday over European debt concerns despite positive job data, with all 10 S&P sectors slipping down led by energy and materials. Rising sovereign bond yields intensified investors\' sentiments and stopped them from buying actions. The CBOE Volatility Index, known as fear index, surged 2.98 percent on Thursday to 34.51. The Spanish government on Thursday sold 3.56 billion euro of 10- year bonds at an average yield of nearly 7 percent, a level seen as unsustainable. The rising yield of government bonds worried investors as the European debt crisis seemed to spread to large economies. On the economic front, the U.S. Labor Department said on Thursday that initial claims for unemployment compensation fell by 5,000 to a seasonally adjusted 388,000 last week. The figure fell to the lowest level in seven months, suggesting that U.S. labor market continued to improve.Meanwhile, the four-week moving average of new jobless claims, a more reliable indicator of the labor market performance as it smoothes out volatile weekly figures, fell by 4,000 to 396,750, the first time for the reading to fall below 400,000 in nearly seven months. Moreover, according to the Philadelphia Federal Reserve Bank, the pace of factory activity in the U.S. Mid-Atlantic region dropped in November. The Dow Jones industrial average dropped 134.86 points, or 1.13 percent, to 11,770.73. The Standard & Poor\'s 500 was down 20.78 points, or 1.68 percent, to 1,216.13. The Nasdaq Composite Index fell 51.62 points, or 1.96 percent, to 2,587.99. Meanwhile, the U.S. dollar rose against major currencies in late New York trading on Thursday as investors\' concerns about the eurozone debt crisis continued to weigh on the euro. The dollar index climbed 0.35 percent to 78.29. As for oil, U.S. crude oil price plunged nearly 4 percent on Thursday after a strong rally on the day before, breaking 100- dollar mark per barrel, as a result of worries about European debt. Light, sweet crude for January delivery plunged 3.77 dollars, or 3.67 percent, to settle at 98.82 dollars a barrel on the New York Mercantile Exchange, snapping all the gains on Wednesday. In London, Brent crude for December delivery also tumbled 3.66 dollars, or 3.27 percent to close at 108.22 dollars a barrel.