An oil-price slump added to turmoil on global markets Monday (March 9).
Crude prices fell as much as 30% before rallying a little.
That after Saudi Arabia's stunning weekend decision to increase output.
Last week the OPEC oil producers' group was set to do the exact opposite, only to see ally Russia refuse to go along.
Now the Saudis are instead flooding the market with cheap oil, undercutting Russia and other rivals.
Analysts say it may be a move to force Moscow back to the negotiating table.
The news added to chaos for equities, already hit by fears of a virus-induced recession.
Asian markets fell as much as 5%.
In Europe, major oil stocks then crumbled, with BP and Shell both down around 17%.
That battered London's oil-heavy FTSE index, which dropped as much as 8%.
Stocks in Italy were the worst hit in Europe though, down over 10%.
It's the European country hardest hit by the coronavirus, with much of its northern region now on lockdown.
A government pledge of massive stimulus doesn't seem to have reassured.
Market watchers like Geo Securities chief Francis Lun bet global stocks have further to fall: (SOUNDBITE) (English) GEO SECURITIES CEO, FRANCIS LUN, SAYING: ''Not too long ago, I think a month ago, Dow Jones industrial average was 29000, now it's about 25000 I think.
It will go down to maybe 22000.
So, we will have a big market correction of at least 20 percent globally.
So buckle your seat belt and hang tight because it will be a rough life.
It will be roller coaster ride.
'' On currency markets the dollar tumbled against euro and yen.
The Japanese currency is up almost 10% over the past two weeks.
It's among traditional safe havens that tend to rise in times of trouble.
Gold is another, with the precious metal now at around seven-year highs.