• The broad-based S&P 500 gained 1.3 percent to 2,959.86, while the tech-rich Nasdaq Composite Index jumped 1.5 percent to 9,320.46.

About five minutes into trading, the Dow Jones Industrial Average stood at 24,497.75, up 1.2 percent.

The broad-based S&P 500 gained 1.3 percent to 2,959.86, while the tech-rich Nasdaq Composite Index jumped 1.5 percent to 9,320.46.