The Dow fell 588.47 points, or 3.6 percent, to 15,871.28. The S&P 500 index slid 77.68 points, or 3.9 percent, to 1,893.21. The Nasdaq composite shed 179.79 points, or 3.8 percent, to 4,526.25 points. The three indexes are down for the year.
View galleryA worker of Tokyo Stock Exchange monitors stock prices …
A worker of Tokyo Stock Exchange monitors stock prices on an electric screen during a trading sessio …
"There is a lot of fear in the markets," said Bernard Aw, market strategist at IG.
The sell-off triggered worries in corporate boardrooms, in government capitals and among ordinary Americans young and old who have been saving for retirement or a down payment on a house.
Heightened concern about a slowdown in China had already shaken markets around the world on Friday, driving the U.S. stock market sharply lower. The rout continued Monday as China's main stock index sank 8.5 percent.
The Dow plummeted 1,089 points within the first four minutes of trading as traders dumped shares. But the fire sale was short-lived. A wave of buying cut the Dow's losses by half just five minutes later.
The U.S. market slide was broad. The 10 sectors in the S&P 500 headed lower, with energy stocks recording the biggest decline, 5.2 percent, amid a continued slump in the price of oil. The sector is down almost 25 percent this year.