MONTREAL (AFP) - Poland's Robert Kubica, driving a BMW Sauber, won a drama-filled Canadian Grand Prix here on Sunday in which pre-race favourite Lewis Hamilton took himself and Ferrari's Kimi Raikkonen out of the race in an early pit lane collision.

German Nick Heidfeld, also driving a BMW, claimed second place and Briton David Coulthard of the Red Bull stable finished third.

After lap 18 of the 70-lap race, Hamilton ploughed into the back of Raikkonen's car while he and Kubica were waiting for the red light at the end of the pit lane.

Kubica leapfrogged Hamilton to the top of the drivers' world championship, four points clear of the Briton, and BMW Sauber now top the constructor's title race.

The Pole's win was the first by a team other than McLaren and Ferrari since October 2006 and fulfilled the Swiss-German team's pre-season ambition to win their first Formula One race.

Toyota's German Timo Glock took fourth place, the best result of his first full Formula One season and Brazilian Ferrari driver Felipe Massa claimed an eventful fifth.

Italian Jarno Trulli completed a good day for the Toyota team with sixth place with Honda's Rubens Barrichello and Toro Rosso's Sebastian Vettel filling the other point-scoring places.

The race started amidst serious concerns over the state of the circuit. Patches of the track surface had crumbled badly during qualifying on Saturday and although running repairs were made overnight, many in the paddock were expecting trouble.

Those concerns translated into a generally cautious attitude amongst the drivers and the start passed without incident.

Nico Rosberg did manage to slip his Williams into fourth place around the outside of Fernando Alonso at the second corner, but it was a clean getaway for Hamilton's McLaren, Kubica and Raikkonen's Ferrari who started first, second and third respectively.

Raikkonen began to put Kubica under serious pressure, the Finn quickly setting the fastest lap of the race but Hamilton was moving well clear in front, only for his lead to be erased when the safety car was deployed after German Adrian Sutil's Force India car caught fire.

As the field bunched up, the leaders ducked into the pits to refuel. Raikkonen and Kubica emerged from the garage ahead of Hamilton, but were held up by a red-light at the end of the pit lane.

Inexplicably, Hamilton did not realise that his two rivals were stationary ahead of him and after pulling away from his garage he barrelled into the back of Raikkonen ending his own race and that of the reigning world champion.

Rosberg was also caught up in the incident and though he was able to continue after some hasty repairs to his front wing, his chances of a points finish was over.

Heidfeld was now leading the grand prix, with Honda's Rubens Barrichello and Williams' Kazuki Nakajima lying second and third.

Heidfeld, his one-stop strategy working perfectly, soon pitted and managed to emerge ahead of Kubica who had emerged unscathed from the pit lane chaos.

Kubica was now leading effectively leading the grand prix but knowing he would need one more fuel stop, the Pole pushed his BMW to the absolute limit to establish a significant lead.

With 22 laps remaining Kubica pitted for the final time, emerging safely in front of his teammate.

Scottish veteran Coulthard was now in third place with a mad scramble for points unfolding behind him.

There was no catching Kubica though and there were scenes of joy in the BMW garage as he crossed the finish line to become the first ever Polish grand prix winner.