It was another day of triple-digit losses on North American markets Thursday as investors showed few signs of wanting to wade back into equities.

The S&P/TSX composite index opened 85 points higher but changed direction within half an hour. By the close, the benchmark index had lost 279 points to 12,796 — its lowest level since the global turmoil in credit markets surfaced last August.

S&P/TSX composite index 3-month chart

That brings the total loss in the index since the close of Monday to more than 900 points. According to Bloomberg, it's the steepest three-day decline in five years.  

Every sector lost ground on Thursday. But once again, energy and other resource stocks led the sell-off.

The TSX energy sub-index was down 2.8 per cent as crude oil futures fell 73 cents to $90.13 US a barrel.

Canadian Natural Resources dropped $3.40 to $64.98.

The metals and mining group was off 4.8 per cent amid a continuing drop in commodity prices. Investors fear that if the U.S. economy goes into recession, worldwide demand for base metals would suffer.

Teck Cominco, a leading copper and zinc producer, was down $1.41 to $31.32 — its lowest level in 19 months. First Quantum Minerals shed $6.69 to $74.56.

Fertilizer stocks plunged following a report that potash inventories were building. Potash Corp. shares dropped $14 to $124; Agrium fell $6.52 to $58.98.

BCE shares fell another 48 cents to $36.53 after falling as low as $35.06 amid continuing market rumours — denied by all the principals — that the telecom's takeover by a group led by the Ontario Teachers' Pension Plan might be reworked. The takeover offer is worth $42.75 a share in cash.  

Markets lose all of 2007's gains

In New York, the Dow Jones industrial average plunged 307 points to 12,159.

Both the TSX and the Dow are now below where they were at the start of 2007.

The market appeared unimpressed by comments from the White House that it would support some kind of economic stimulus package.

The economic picture south of the border remained bleak, as new reports showed a sharp drop in regional manufacturing activity and the U.S. housing market slumped to multi-year lows.

A report by Merrill Lynch that it lost a larger-than-expected $9.9 billion US didn't help the mood, either.

The Russell 2000 index — which tracks 2,000 smaller American companies — hit a low that was 20 per cent below its high mark set last July. That satisfied the technical definition of a bear market. 

The TSX, by comparison, is down about 12.6 per cent from its high last October; the Dow is down about 14.8 per cent. A drop of more than 10 per cent from the previous high qualifies as a market correction.  

Donald Coxe, global portfolio strategist at BMO Financial Group, thinks there's more selling to come. 

"We're in a bear market now, both in New York and Toronto," he told CBC News. "It'll not be a big bear market. We're probably halfway from the top to the bottom.