The Dow Jones index fell 1.02% to 33,530.83 points, the Nasdaq lost 1.98% to 11,799.16 points and the S&P 500 dropped 1.58% to 4,071.63 points. The VIX index, known as "fear", which measures market volatility, jumped 15%.
"It must be said that this is the first day since March 22 where the major indices decline by more than 1%," said Steve Sosnick.