Toronto stocks ended lower on Thursday weighed down by Bombardier and Manitoba Telecom and investor worries about the health of the economy and terrorism.

The S&P/TSX composite index slid 45.82 points to finish at 8,555.90. Volume was heavy with 280 shares changing hands.

Three names led the decline: Bombardier, Nortel Networks and Manitoba Telecom Services.

Manitoba Telecom stock slumped after it agreed to buy Allstream for $1.7 billion. Manitoba Telecom shares fell $5.30 to $48.00, dragging the telecoms sector down 3.87%.

The industrials sector fill 1.3% as investors punished Bombardier after it reported a loss on Wednesday and unveiled plans to restructure its rail unit. Bombardier’s class B shares lost 46¢ at $5.98. It was the day’s most active stock with 20.9 million shares traded.

The technology sectors slid 1.34% as bellwether Nortel Networks dropped 24¢ to $7.22 on a volume of 20.6 million shares.

On the upside, the utilities and materials group both rose.

The gold sub-index, a component of the materials group and investors safe haven of choice, climbed 2.3%. Barrick Gold gained 11¢ to $29.40, while Placer Dome added 70¢ to $22.90.

The junior S&P/TSX Venture composite index gained 16.30 points to close at 1,858.37.

On Wall Street, stocks ended slightly lower on as reports that Pakistani forces were closing in on a key al Qaeda figure tempered security fears.

The Philadelphia Federal Reserve’s survey showed a surprise drop in manufacturing in the U.S. Mid-Atlantic region in March.

The Dow Jones industrial average closed down 4.52 points at 10,295.78. The S&P 500 slipped 1.44 points to at 1,122.31. The tech-heavy Nasdaq composite index fell 14.32 points to 1,962.44.