Shares are suffering a fresh bout of market jitters as the European markets close for the day.
Earlier on Thursday, US stocks had clawed back some ground, a day after suffering their worst losses in eight months.
The Dow Jones index was down 338 points, or 1.32%, at 25,260 points and the S&P was down a similar amount at 5,466. The Nasdaq was 0.77% lower.
In London, the UK’s FTSE 100 share index was down 1.2% at 7,063.
Earlier, markets in Asia had plunged to a 19-month low.
Markets in Asia had followed US stocks, which slumped on Wednesday.
Japan’s benchmark Nikkei 225 dropped 3.9%, its steepest daily drop since March. In China, the Shanghai Composite fell 5.2% to its lowest level since 2014.
Kim Gittleson, New York business correspondent
For traders who had got used to the seemingly inevitable march of US stock markets ever higher, Wednesday was a bit of a shock.
Here’s just one reason why: the S&P 500 didn’t record a single move up or down of more than 1% during the third quarter of 2018. That hasn’t happened since 1963, according to LPL Financial.
So what led investors to head for the exit?
As ever, it’s almost impossible to pinpoint one reason for the sell-off.
The consensus seems to be a combination of rising interest rates, tariffs and inflation led investors to worry that fourth-quarter earnings season, which begins on Friday, won’t be as record-breaking as prior quarters.
But when it comes to one of those concerns – inflation – investors got to breathe a sigh of relief on Thursday.
Just before US markets opened, the September reading of the consumer price index showed that prices rose by just 0.1% during the month, below expectations.
After the release, the mood on the floor of the New York Stock Exchange was almost instantly lightened, as the lower-than-expected reading tempered concerns that the US Federal Reserve will be forced to increase interest rates at a faster pace than expected.
The question is if calm will once more prevail on Wall Street – or if Wednesday’s dip was a harbinger of a turbulent earnings season to come.
Trump attacks ‘crazy’ Fed
US markets have done better than expected this year, bouncing back after turmoil early in the year to set new records over the summer.
But the Federal Reserve is raising interest rates, with the latest hike coming last month, and more increases are likely to come.
The Fed last month abandoned its description of its policy as “accommodative”, reflecting a view that the economy is strong enough not to need the kind of stimulus it received in the after-math of the financial crisis.
The prospect of dwindling US stimulus has been compounded by a trade war between the world’s two largest economy – which the IMF has warned could harm growth.
US President Donald Trump has been particularly critical of the Fed’s rate rises, breaking with tradition in the US where presidents are expected to respect central bank independence.
“The Fed is making a mistake,” he told reporters on Wednesday. “I think the Fed has gone crazy.”
However, analyst Michael Hewson of CMC Markets said it was “too simplistic just to blame the Federal Reserve” for market turmoil.
“There are a number of factors,” he told the BBC. “Obviously, concerns about slowing growth – the IMF downgraded its global growth forecast for the global economy, citing emerging market concerns,” he said.
David Madden, market analyst at CMC Markets UK. said there were lots of reasons worrying the market: “Traders are nervous about the relatively high bond yields in the US, the potential fiscal fight between Brussels and Rome, and poor global trading relations.
“Some economists have been warning about a possible economic slowdown, and the lowering of the global growth forecast by the IMF has got dealers worried.”