The message US investors took away from the Federal Reserve yesterday was that higher interest rates were coming, and soon.
That sent stocks and gold prices lower and bond yields sharply higher.
The Dow Jones industrial average lost 114.02 points, or 0.7%, to 16,222.17. The Dow fell as much as 209 points before erasing some of its loss.
The Standard & Poor's 500 index dropped 11.48 points, or 0.6%, to 1,860.77 and the Nasdaq composite lost 25.71 points, or 0.6%, to 4,307.60.
The Fed voted to cut its monthly bond purchases from 65 billion dollars to 55 billion dollars, in line with what analysts were expecting.
Despite severe winter weather in January and February, the Fed said economy had recovered enough for it to continue reducing the bond buys, which are aimed at keeping long-term interest rates low.
The Federal Reserve also said the vast majority of its policymakers believed it would be appropriate for the central bank to raise short-term interest rates starting in 2015.
The Federal Funds rate, traditionally the Fed's main tool for regulating the health of the economy, has been near zero since 2008.
"We think they are acknowledging for the first time that short-term rates will rise in the future," Chris Rupkey, chief financial economist with Bank of Tokyo-Mitsubishi UFJ, said.
"And that future is not that far away. A normal economy will need a normal interest rate."
Traders were also confused after newly appointed Fed chairwpman Janet Yellen implied that the Fed's time frame for raising interest rates was closer to the first half of 2015, sooner than many had expected.
At a press conference, Ms Yellen was asked how much time would need to pass between when the Fed ends its bond-buying programme - which is expected to end in the second half of 2014 - and when the Fed would raise interest rates.
She responded that the Fed could consider raising interest rates in "six months or that type of thing" from when the bond-buying programme would end.
A timetable of six months was much sooner than investors had predicted. So whether or not Ms Yellen meant the "six months" as a definitive time table or a rough estimate based upon where the economy might be in a year, the market took her at her word, strategists said.
Stock and bond prices steepened in their decline after she made her comments.
"It creates a haze of uncertainty," said Andres Garcia-Amaya, global market strategist with JP Morgan Funds. "As we get closer to 2015, we should expect more volatility like this."
The reaction to Ms Yellen's remarks and the Fed's announcements was far more noticeable in the bond market.
The yield of the 10-year US Treasury note, a benchmark for many kinds of loans including mortgages, rose to 2.77% from 2.67% on Tuesday, a large move.
The sell-off was even more pronounced in two-year and five-year Treasury notes. The yield on the two-year note jumped to 0.42% from 0.35% and the five-year note's yield rose to 1.7% from 1.54%.
The US dollar had its biggest one-day gain since August 2013 and gold had its worst day since December. In afterhours trading, gold was down 28.20 dollars, or 2%, to 1,330.80 dollars an ounce.