New worries that Europe and the United States are sinking into a recession roiled global stock markets on Thursday, while panicky investors pushed gold and US Treasury bonds to fresh records.
The worldwide sell-off came after Wall Street investment bank Morgan Stanley warned that the US and eurozone economies were "dangerously close" to a double-dip recession.
Stocks were further punished by a fresh round of gloomy economic data from the United States and growing doubts about the ability of European banks to withstand the eurozone's debt crisis.
The Dow Jones Industrial Average was down 3.7 percent at the closing bell, while the broader S&P 500 slumped 4.5 percent and the tech-heavy Nasdaq Composite plummeted 5.2 percent.
Banking stocks were hit hard, with Bank of America plunging 6.0 percent and Citigroup falling 6.3 percent.
Losses were even worse in Europe, as London stocks closed down 4.5 percent, Paris fell 5.5 percent and Frankfurt dropped 5.8 percent.
A report in The Wall Street Journal that the US Federal Reserve was worried about the liquidity of major European banks contributed to the sell-offs in European markets.
French lenders came under especially intense pressure, with Societe Generale losing more than 12 percent.
"The concern is that the escalating European sovereign debt crisis -- which is now engulfing larger countries -- and the potential fall-out for the banking sector and financial markets, could provide a killer blow," said Nick Kounis, an economist at ABN Amro.
The toxic cocktail of negative news sent gold flying to a new record price of $1,828.80 per ounce as investors sought the precious metal, seen as a safe haven in times of financial turmoil.
Investors also flocked to the traditional safe haven of US government debt, briefly pushing down the yield on the 10-year Treasury to a historic low of 1.974 percent, breaking the previous record set during the 2008 crisis.
The 10-year yield later recovered to 2.07 percent. Bond prices and yields move in opposite directions.
"This is another flight to safety. We got the typical move in gold, in the Treasuries. You're pretty much seeing panic all over again," said Marc Pado, chief US market strategist for Cantor Fitzgerald.
Oil prices slumped as traders fretted that an economic downturn could deeply erode global energy demand. New York's main oil contract lost $5.20 to close at $82.38 per barrel -- a plunge of nearly six percent. In London, Brent North Sea crude fell more than three dollars.
The US Federal Reserve Bank of Philadelphia said that manufacturing in the mid-Atlantic states took a sharp hit in August, compounding fears that the United States was slipping back into recession.
Investors were also spooked by US government data showing that new claims for unemployment insurance rose by 9,000 last week.
"A negative feedback loop between weak growth and soggy asset markets now appears to be in the making in Europe and the US," Morgan Stanley said in a bleak new assessment of the global economy, which also contained pointed criticism of US and European policy-makers.
The bank cut its 2011 global growth estimate to 3.9 percent from 4.2 percent, and the 2012 forecast to 3.8 percent from 4.5 percent.
Mature economies could expand by just 1.5 percent this year and next, it said, citing "recent policy errors in the US and Europe plus the prospect of further fiscal tightening in 2012."
In the forex market, the dollar gained against the euro. The greenback was trading for $1.4337 against the euro at 2100 GMT on Thursday, compared to $1.4428 at the same time Wednesday.
"The euro is seen as a risky currency because the debt crisis remains unresolved, so it is losing some ground," said Samarjit Shankar, managing director for foreign exchange at BNY Mellon.
The dollar slipped slightly against the yen, falling to 76.52 yen from 76.54 on Wednesday.
It rose against the Swiss franc, climbing to 0.7936 francs from 0.7897 a day earlier.
The dollar gained against the British pound, strengthening to $1.6520 versus the pound from $1.6545 on Wednesday.