REUTERS/Shannon Stapleton
A trader sits outside the New York Stock Exchange October 6, 2008.
The Dow was down as much as 150 points to 16,420. The S&P 500 was off 19 points, nearly 1%, to 1,920. The NASDAQ was off 33 to 4,351.
Intel was down 3% on major volume.
Target also fell after profits missed forecasts.
Headlines about Russian troop movement near the border of Ukraine is one possible explanation for what's spooking stocks.
There's also been a ramp-up in talk that the Fed could accelerate the end of its dovish environment monetary, whether through accelerating the tapering of its bond-buying program or raising interest rates sooner than expected.