NEW YORK (Reuters) - U.S. stocks fell sharply at the open on Tuesday on concerns about the impact of lower oil prices on the global economy and the effect of political turmoil in Greece on the euro zone.
The Dow Jones industrial average fell 139.81 points, or 0.78 percent, to 17,712.67, the S&P 500 lost 16.9 points, or 0.82 percent, to 2,043.41 and the Nasdaq Composite dropped 51.08 points, or 1.08 percent, to 4,689.61.
Overnight, the Shanghai Composite Index dropped more than 5 percent, its biggest drop in more than five years, also weighing on investor sentiment.
(Reporting by Rodrigo Campos; Editing by Nick Zieminski)