Toronto stocks dropped Wednesday, deepening a recent pullback, as the resource sectors were hit hard once again by falling commodity prices.

The S&P/TSX composite index fell 128.46, or 1.09%, to 11,648.74.

Seven of the 10 TSX main sub-groups were down, with the energy sector off 2.57%

Light, sweet crude for October delivery closed down 75¢ at US$63.22 a barrel.

Canadian Natural Resources Ltd. announced it is buying Anadarko Canada Corp., a subsidiary of Anadarko Petroleum Corp., for about US$4.1 billion. Canadian Natural Resources fell $1.83, or 3.57%, to $49.46.

The materials index fell 2.50%, while the gold sub-index fell 3.71%.

Gold futures fell $10.30 to US$586 an ounce.

Iamgold Corp. struck a deal to acquire Cambior Inc. in a US$1.33billion stock-swap merger. Iamgold shares fell $1.47, or 12.79%, to $10.02, while Cambior gained 47¢, or 12.81%, to $4.14.

The S&P/TSX Venture composite index lost 35.33 points, or 1.36%, to 2,570.22.

In New York, markets were mixed as investors concerned themselves again with a possibly slowing U.S. economy.

The Dow Jones industrial average fell 15.93 points to 11,527.39, the S&P 500 dipped 1.79 point to 1,316.28 and the Nasdaq composite index gained 1.06 to 2,228.73.