US stocks dropped in opening trade Monday as Greece neared default on its debts and possibly a turbulent exit from the eurozone.

Five minutes into trade, the Dow Jones Industrial Average was at 17,807.25, down 139.43 points (0.78 percent). The broad-based S&P 500 fell 16.20 (0.77 percent) to 2,085.29, while the tech-rich Nasdaq Composite Index dropped 53.12 (1.05 percent) to 5,027.38.