Wall Street stocks ended lower Tuesday as top US economic officials warned the US economy faces continued risks, causing the market to give back some of the gains from the prior session. At the closing bell, the Dow Jones Industrial Average stood at 24,206.86, down 1.6 percent, after pulling back from the 3.9 percent surge Monday. The broad-based S&P 500 dropped 1.1 percent to 2,922.94, while the tech-rich Nasdaq Composite Index shed 0.5 percent to 9,185.10. jmb/hs