* The Toronto Stock Exchange's S&P/TSX composite index ended down 121.94 points, or 0.78 percent, at 15,589.39, its lowest close since March 9.

* Energy shares were the biggest drag on the index, with Enbridge Inc falling 2.9 percent to C$40.09 and Suncor Energy Inc down 2.0 percent at C$42.05.

* U.S. crude oil futures settled 0.5 percent lower at $62.06 a barrel.

* Technology shares fell 1.0 percent, while the materials group, which includes precious and base metals miners and fertilizer companies, also lost 1.0 percent.

* The TSX posted one new 52-week high and seven new lows. Eight of the index's 10 main groups ended lower.

* The largest percentage gainer on the TSX was Novagold Resources Inc, which rose 7.8 percent, while the largest decliner was Ivanhoe Mines Ltd, down 7.3 percent.

* Among the most active Canadian stocks by volume were Aurora Cannabis, down 1.4 percent to $10.80; Bombardier B, up 0.5 percent to $3.77 and Neovasc Inc, down 8.6 percent to $0.16.

(Reporting by Fergal Smith; Editing by Tom Brown)