The Dow Jones industrial average <.DJI> gained 337.17 points, or 2.87 percent, to end unofficially at 12,103.43. The Standard & Poor's 500 Index <.SPX> gained 35.95 points, or 2.98 percent, to finish unofficially at 1,241.30. The Nasdaq Composite Index <.IXIC> gained 80.59 points, or 3.19 percent, to close unofficially at 2,603.73.

(Reporting by Edward Krudy; Editing by Jan Paschal)