The Dow Jones Industrial Average lost another 2.1% or 545.9 points to 25,052.8 points and is around 1800 points off its high.
The S&P 500 dropped by the same amount, while UK and European equities lost an average of 1.9%.
"Sell-offs happen, the third quarter of 2018 was a quiet three months," IG market analyst Chris Beauchamp said.
"But until proved otherwise, this is still a dip, not the next 2008. Risk management remains key, but the bull market is intact."
ASX futures were down 47 points after yesterday's 2.7% loss.
While equities suffered, the big winner was gold, which surged by as much as 3% to a high of US$1230 an ounce.
Gold was helped along by weaker-than-expected US inflation data which could impact further interest rate h...