Wall St opens lower on heightened security worries

US stocks opened lower on Tuesday as investors fled risky assets after Turkey shot down a Russian warplane, even as data pointed to stronger U.S. economic growth.

The Dow Jones industrial average was down 48.5 points, or 0.27 percent, at 17,744.18, the S&P 500 was down 7.45 points, or 0.36 percent, at 2,079.14 and the Nasdaq composite index was off 32.15 points, or 0.63 percent, at 5,070.33.