The Fed said it was cutting its monthly bond purchases by another $10 billion, citing an improvement in economic activity in the United States, even as the crisis in emerging markets flared.

Investors remained concerned about slowing economic growth and increasing credit risk in China, as well as perceptions of instability in emerging markets. Doubts about China, coupled with extreme volatility in the Argentine peso and the Turkish lira, have raised questions about the risks of investing in emerging markets.

The Fed "obviously felt there was nothing in the U.S. data that would give them cause to pause," said Stephen Wood, chief market strategist, North America, at Russell Investments. "The Fed, while it may be easing up on the accelerator, will not be looking for the brake pedal anytime soon.

"There's a momentum right now towards a risk-off strategy, and emerging markets are at the forefront of that global sentiment," added Wood, who noted the Fed's mandate was a domestic one.

The Toronto Stock Exchange's S&P/TSX composite index <.GSPTSE> closed down 44.56 points, or 0.33 percent, at 13,643.10.

The benchmark index, with its high concentration of resource shares, lost about 2.5 percent in the last week.

Despite the selloff, Wood said it would be wise to remain cautious about natural resource shares as China's economic growth slows down.

Seven of the 10 main sectors on the index were in the red on Wednesday. Financials, the index's most heavily weighted sector, fell 0.9 percent.

Bank of Nova Scotia (>> The Bank of Nova Scotia), which has significant exposure to emerging markets, with operations in Latin America and Asia, dropped 0.9 percent to C$61.35.

Royal Bank of Canada (>> Royal Bank of Canada) said it will sell its Jamaican banking operations to Sagicor Group Jamaica Ltd . RBC shares slipped 1.1 percent to C$68.77.

Shares of energy companies gave back 0.7 percent. Suncor Energy Inc (>> Suncor Energy Inc.) shed 0.7 percent to C$36.44, and Canadian Natural Resources Ltd (>> Canadian Natural Resources Limited) slipped 0.8 percent to C$36.

Gold-mining shares jumped 3.3 percent, reflecting gains in the price of bullion. Barrick Gold Corp (>> Barrick Gold Corp.) climbed 4.2 percent to C$21.83.

In other corporate news, Canadian Pacific Railway (>> Canadian Pacific Railway Limited) reported a weaker-than-expected quarterly profit, but it forecast adjusted earnings would climb at least 30 percent in 2014 on stronger revenue. The stock advanced 4.3 percent to C$165.

Shares of AGF Management Ltd (>> AGF Management Limited) tumbled 6.3 percent, to C$11.63, after the fund manager posted a smaller-than-expected fourth-quarter profit as the redemption of a single legacy account helped trim assets under management by 12.1 percent. The stock was the biggest percentage decliner on the index.

($1=$1.11 Canadian)

(Editing by Peter Galloway and Leslie Adler)

By John Tilak