U.S. stocks finished sharply lower on Monday and were on track for their worst quarter in four years as investors worried about the health of China's economy and its potential impact on a U.S. interest rate increase.
The Dow Jones industrial average fell 312.47 points, or 1.92 percent, to 16,002.2, the S&P 500 lost 49.49 points, or 2.56 percent, to 1,881.85 and the Nasdaq Composite dropped 142.53 points, or 3.04 percent, to 4,543.97.
Health care, especially the biotech sector, and energy stocks fell the most.
All three major averages were in correction territory, or more than 10 percent below their 52-week highs.
"The big concern here is the market has deteriorated to a point that now even the leadership is faltering," said Lance Roberts, head of Streettalklive.com.
Drugmakers continued to fall, extending a sell-off that began last week when news organizations reported on big price hikes for newly acquired drugs.
Among the big losers was Valeant, which saw shares plunge more than 15 percent on news that Democrats are pressing a Republican committee chairman to force the pharmaceutical firm to turn over documents tied to a price hike from earlier this year.
Profits at Chinese industrial companies fell 8.8 percent, fresh data showed, pushing down shares of raw material producers and energy companies. Oil prices fell more than 2 percent.
Meantime, U.S. consumer spending rose more than expected in August, data showed on Monday, appearing to add to the case for an interest rate increase this year.
The Federal Reserve held off from raising rates at its September meeting, citing concerns about the global economy, notably China, among other factors. New York Federal Reserve President William Dudley on Monday added to expectations for a rate increase, suggesting the central bank could pull the trigger as soon as October. Several other Fed officials are scheduled to speak during the week, including Chair Janet Yellen on Wednesday.