(Adds portfolio manager comment, details; updates prices)
* TSX ends down 278.59 points, or 2.19 percent, at 12,448.21
* Nine of the TSX's 10 main groups fall
By Alastair Sharp
TORONTO, Jan 7 (Reuters) - Canada's benchmark stock index slid on Thursday to its lowest level in nearly two-and-a-half years as investors worried about China's equities market and oil prices pushed ever lower.
Losses were broad and deep, with energy stocks retreating 4.2 percent, industrials shedding 2.5 percent and financials down 2.2 percent. Thirty-nine stocks posted fresh 52-week lows.
"Right now people are taking maximum negativity and factoring that out into the marketplace," said Irwin Michael, a portfolio manager at ABC Funds. "The path of least resistance is down."
The Toronto Stock Exchange's S&P/TSX composite index ended the day down 278.59 points, or 2.19 percent, at 12,448.21.
That was its seventh straight decline and sharpest one-day loss since Dec. 7, pushing the index to its lowest level since August 2013.
Of the 10 main sectors, only the materials group closed in positive territory, thanks to gains in gold miners as bullion hit a seven-week high.
Tumult in China, where equities trading was suspended for a second time this week, has hurt markets across the globe as investors worry about weaker demand from the world's second-largest economy.
Oil slid below $33 a barrel as China's troubles added to concerns about near-record production and massive stockpiles of unwanted crude and refined products.
The most influential weights on the Canadian index included Canadian Natural Resources, which lost 6.2 percent to C$27.53, and Suncor Energy Inc, which declined 2.4 percent to C$33.30.
U.S. crude prices settled down 2.1 percent at $33.27 a barrel, while Brent lost 1.6 percent to $33.69 a barrel.
Royal Bank of Canada declined 1.8 percent to C$70.25 and Toronto-Dominion Bank <TD.TO lost 2.2 percent to C$51.03.
Gold futures rose 1.5 percent to $1,109 an ounce, and the top five gainers of the index were all precious metal miners.
Copper prices declined 2.1 percent to $4,524.15 a tonne. (Editing by G Crosse)