The 1.3 percent drop was the seventh straight session of losses for the Toronto Stock Exchange's S&P/TSX composite index <.GSPTSE>, and its first day trading below 14,000 since January.

"There is a 'Sell Canada' theme going on," said Diana Avigdor, portfolio manager and head of trading at Barometer Capital Management. "At some point we're going to have a respite, but that's not an investment thesis."

Five of the six most influential weights were financial stocks, which overall lost 1.5 percent. Toronto-Dominion Bank (>> Toronto-Dominion Bank) fell 1.7 percent to C$50.99 and Royal Bank of Canada (>> Royal Bank of Canada) declined 1.4 percent to C$73.52.

The index lost 184.87 points to close at 14,001.37, with the energy group falling 2.8 percent and materials names shedding 3.1 percent. It fell as low as 13,956.05 during the session, a level last seen on Jan. 14.

Some one-fifth of Canada's index sells raw materials or energy products, and investors fret that China's transition to a more consumer-focused and slower-growth economy will plague their prospects.

"I'm somewhat kind of pessimistic on China. I certainly don't see a crash imminent, but the economy is slower than I would've thought," said John Johnston, chief strategist at Davis-Rea. He said a global recession could be unfolding.

Chinese stocks slumped the most in eight years, sending commodity prices falling. [O/R]

Among oil and gas companies, Canadian Natural Resources Ltd (>> Canadian Natural Resources Limited) slid 1.6 percent to C$30.20, while Suncor Energy Inc (>> Suncor Energy Inc.) retreated 1.1 percent to C$32.72 and Encana Corp (>> Encana Corporation) lost 5.8 percent to C$9.67.

Of the index's 10 main sectors, only healthcare notched a gain, thanks to a 3.3 percent gain in Valeant Pharmaceuticals (>> Valeant Pharmaceuticals Intl Inc), the index's largest company by market capitalization.

Declining shares outnumbered advancers by a more than 13-to-1 margin and 57 companies hit fresh 52-week lows.

Restaurant Brand International (>> Restaurant Brands International Inc), formed out of Burger King's takeover of Canadian coffee and doughnut chain Tim Hortons, was among the few gainers. Its shares rose 3.9 percent to C$54.21, after its earnings cheers investors.

(Additional reporting by Solarina Ho; Editing by Meredith Mazzilli)

By Alastair Sharp