(Updates with details)
TORONTO, Feb 6 (Reuters) - The Toronto Stock Exchange's main index turned negative on Wednesday, falling along with tech and energy heavyweights Research In Motion RIM.TO and EnCana Corp (ECA.TO).
The S&P/TSX composite index .GSPTSE was down 33.41 points, or 0.3 percent, at 12,898.54. It was up as much as 135 points earlier in the session.
The relatively small information technology sector tumbled 2.9 percent, yanked lower by the volatile shares of BlackBerry maker RIM, which fell C$3.77 to C$85.15.
Although natural gas futures remained flat, the price of U.S. crude oil slid sharply midway through the session, driving down TSX oil and gas producers.
The sector slipped 0.7 percent, with EnCana down C$1.16 at C$65.75 and Petro-Canada PCA.TO off C$1.18 at C$43.39.
Cameco Corp (CCO.TO) edged lower by 20 Canadian cents, to C$32.12, after the world's top uranium producer said quarterly profit jumped more than 50 percent. For details, see: [nN06269462]
On the upside, BCE Inc (BCE.TO), Canada's No. 1 telecom firm, rose 82 Canadian cents to C$35.37 as investors cheered its fourth-quarter results. For details, see: [nN06299216]
But gold firms, up 1.7 percent as a group, were the biggest weighted gainers.
Vancouver-based Goldcorp climbed 85 Canadian cents to C$35.73. Toronto-based Barrick advanced 70 Canadian cents to C$48.90.
The TSX index has dropped nearly 3 percent in the past two sessions.
$1=$1.00 Canadian Reporting by Jonathan Spicer; editing by Rob Wilson