Wall Street sells off on growth concerns; volatility picks up

... taken away, a tailwind turning into a headwind," said Michael O'Rourke, chief market strategist at JonesTrading in Greenwich, Connecticut. The Dow Jones industrial average .DJI ended down 334.97 points, or 1.97 percent, at 16,659.25; the S&P 500 ...

http://www.reuters.com/article/2014/10/10/us-markets-stocks-idUSKCN0HY11U20141010?feedType=RSS&feedName=businessNews