Wall Street shares have extended their declines with a renewed bout of selling amid worries about technology and retail stocks.
The Dow Jones Industrial Average fell by around 500 points, or 2%, early in Tuesday trading, having dropped 400 points the day before.
A torrid session on Monday saw more than $130bn in market value wiped off the so-called FAANG stocks – Facebook, Amazon, Apple, Netflix and Google owner Alphabet.
That came after a report in the Wall Street Journal claimed Apple had cut production on all three of its iPhone models launched in September – adding to worries about its sales growth.
The sell-off marks the latest period of volatility for the New York market and Tuesday's trading saw the Dow fall back to its level at the start of 2018.
Oil was also a major faller, with the price of a barrel of Brent crude slipping by 4% to less than $64 amid wider concerns about the global economy.
In London, the FTSE 100 closed nearly 1% lower on Tuesday while stock indices in France and Germany also saw significant falls.
On Wall Street, Apple fell by 3% while Amazon lost nearly 4% and Microsoft slipped 3%.
Boeing was the biggest faller on the Dow Jones, sliding 3% as it cancelled a conference call to discuss systems on the 737 MAX model that crashed in Indonesia last month.
US retailers were also under pressure with Target down 10% after posting lower than expected third quarter earnings and department store operator Kohl's off 11% as its full-year profit expectations disappointed investors.
Michael Antonelli, managing director for institutional sales trading at Robert W. Baird said: "It's a growth-related sell-off. It's not a specific name.
"People think growth has peaked and earnings have peaked.
"Some of the big retailers are now cracking and that's just adding fuel to the fire."
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