Dow Jones down 500 points. The tech-heavy Nasdaq index fared even worse, slumping 5 per cent. These numbers constitute what brokers generally call a bad day on the market.

Heavy trade across the board saw no one sector spared, with margin selling fuelling the crash. And it wasn’t an exercise in switching to safe havens either – oil fell 5 per cent, gold and silver hardly budged, and with 10 year treasuries well under 3 per cent, there’s not a lot of enthusiasm for switching to bonds.

No single catalyst sparked the trouble. The usual culprits (Euro debt, soft employment numbers) played a part, but there’s a real sense of doom plaguing Wall Street.

Back home, margin lenders will be on the phone already, with the big banks, BHP and some of the other ASX100 members likely to be smashed on opening. As trade progresses, we’ll find out whether this is a serious bear market, or just an overreaction.

Bargain hunters could save the day in afternoon trade, but we should still see another 100 point loss on the All Ords. Bad news from anywhere would push that out to 200.