Worries over China's economic slowdown and the possible end to the US Federal Reserve's stimulus sent global markets into a tailspin Thursday.
From Tokyo to Turkey and Paris to Wall Street, stocks racked up steep losses across the board, gold and oil prices sank, and the dollar jumped higher against most other currencies.
A two-percent-plus drop in US stocks completed the dismal day for investors.
The Dow Jones Industrial Average lost nearly 354 points, or 2.3 percent, to 14,758.32. It was the blue chip index's largest points loss since November 9, 2011.
The broader S&P 500 sank 2.5 percent to 1,588.19, while the tech-rich Nasdaq Composite tumbled 2.3 percent to 3,364.63.
For the US markets, the plunge followed one percent losses Wednesday sparked by Chairman Ben Bernanke's statement that the Fed could begin pulling back its $85 billion-a-month stimulus program late this year and wind it up by mid-2014.
US bond prices jumped to their highest levels in more than one year and, despite the Fed's reasoning that the US economy is strengthening, investors took it as bad news for the easy money that has helped power US markets to record highs this year.
Michael Hewson, Senior Market Analyst at CMC Markets UK, called the reaction "a classic case of perverse logic," given that Bernanke was clearly signaling stronger US growth.
"The sell-off was given added momentum by rising concerns of a credit crunch in China as well as a simply horrible manufacturing PMI print, as concerns about the trajectory of Chinese growth continued to build up," he said.
China's troubles appeared to mount, with Interbank interest rates surging after the People's Bank of China tightened the spigot on funds for overextended lenders and HSBC said its manufacturing purchasing managers index indicated the sector was in contraction for the second straight month.
As a result, Shanghai's market fell 2.8 percent and Hong Kong 2.9 percent, while Tokyo's Nikkei 225 index took a smaller hit, losing 1.7 percent.
In Europe, the damage was 3 percent or more in major bourses: Euro STOXX 50 index lost 3.6 percent; Germany's Dax 3.3 percent, the CAC 40 3.7 percent and in London, the FTSE 100 index dropped 3.0 percent.
In some secondary markets the damage was heavier, with Turkey -- where political strife also drove sellers -- losing 6.8 percent.
In other markets, gold lost 6.5 percent to $1,283.90 an ounce, its lowest level since September 2010, and oil futures sank nearly $4 in London to $102.15 a barrel.
The dollar bounced 1.0 percent against the yen, to 97.36 yen, while the euro gave up 0.6 percent on the dollar, to $1.3220.
The combination of worries over China and the foreshadowing of possible real monetary tightening in the United States -- still only expected in 2015 -- was a potent blow to investor expectations.
Despite Bernanke's repeated exhortation that Fed moves will depend entirely on economic indicators, the market focused on the possible end of quantitative easing, which has kept interest rates low and powered the market.
"Market participants concluded that the Fed sounds as if it is leaning more in favor of tapering its asset purchases sooner rather than later," said Patrick O'Hare of Briefing.com.
"There was a demonstrative judgment in the market that the Fed chairman didn't give the market what it wanted."
"It does feel as if the Fed chairman has pulled the rug from underneath the stock market rally, and he certainly seems to have dealt a killer blow to gold," said analyst Yusuf Heusen at trading firm IG.
For the US markets, the falls did not erase the strong gains from the beginning of the year. The S&P 500 remains up 11.4 percent for the year, and the Dow remains up 12.6 percent.
But in Europe the day's losses were more disappointing, taking the EuroSTOXX 50 into the red, down 1.5 percent since the beginning of 2013.
O'Hare said the key driving force is the bond markets' reaction, wholly based on expectations since neither the Fed nor other major central banks has actually suggested raising interest rates.
"The scare factor for bond holders is that central banks aren't throwing off dovish signals with reckless abandon anymore," said O'Hare.
"The Bank of Japan didn't go out of its way to calm concerns about the volatility in its stock and bond markets; the People's Bank of China isn't injecting liquidity to calm its markets."