Wall Street stocks tumbled Thursday due to unease over Greece, volatility in the bond market and worries about growth after the IMF cut its US economic forecast.
The Dow Jones Industrial Average fell 170.69 points (0.94 percent) to 17,905.58.
The broad-based S&P 500 dropped 18.23 (0.86 percent) to 2,095.84 while the tech-rich Nasdaq Composite Index fell 40.11 (0.79 percent) to 5,059.12.
"There's cautiousness in the air," said Peter Cardillo, chief market economist at Rockwell Global Capital.
The IMF cut its US growth projection to 2.5 percent from the prior forecast of 3.1 percent. IMF chief Christine Lagarde called on the Federal Reserve to hold off on a rate hike in 2015, saying growth conditions are not yet firm enough for it.
Meanwhile Greece was still apparently far from agreement over new financing from official creditors, though one flash point -- a large debt repayment slated for Friday -- was finessed when the IMF permitted Athens to bundle all its June payments, 1.6 billion euros ($1.8 billion) worth, into one due on June 30.
Investors are looking ahead to the May US jobs report and a policy announcement from the Organization of the Petroleum Exporting Countries. Both are scheduled for Friday.
Wireless carrier T-Mobile US and pay-television company Dish Network rose on reports saying they are in talks to combine. T-Mobile rose 2.6 percent and Dish jumped 4.9 percent.
Sprint, a rival and once considered likely to take over T-Mobile, fell 6.1 percent, amid worries that it was falling behind in market share and still losing money.
Packaged food company JM Smucker dropped 3.8 percent after reporting a loss of $45.3 million for the quarter ending April 30.
Bond prices rose. The yield on the 10-year US Treasury dropped to 2.30 percent from 2.37 percent Wednesday after rising as high as 2.42 overnight. The 30-year declined to 3.04 percent from 3.10 percent. Bond prices and yields move inversely.