BMW Sauber's Robert Kubica took his and his team's first Formula One victory in a dramatic Canadian Grand Prix as Lewis Hamilton crashed out in the pits.

Kubica survived an intervention by the safety car and a crumbling track that provoked errors from several drivers.

Hamilton's chances were dashed when he crashed into the back of Ferrari's Kimi Raikkonen as the Finn waited on a red light at the end of the pit lane.

Nick Heidfeld completed a BMW one-two with Red Bull's David Coulthard third.

The Toyota of Timo Glock was fourth, ahead of Ferrari's Felipe Massa.

The Brazilian passed the second Toyota of Jarno Trulli two laps from the end when the Italian was delayed when his team-mate an error in front of him.

Rubens Barrichello's Honda was seventh - the Brazilian had been running fourth, holding off the Toyotas, when he made an error and slid wide on the slippery track with 10 laps remaining.

Toro Rosso's Sebastian Vettel took the final points place, holding off Heikki Kovalainen's McLaren in the closing laps.

Hamilton looked to have the race in the bag until the intervention by the safety car.

He had built up a 7.1-second lead over Kubica when the safety car was deployed on lap 17 so that marshals could remove the stranded Force India of Adrian Sutil.

All the leading drivers came in for fuel and tyre stops as soon as the pit lane was open on lap 19.

But as they finished their stops, the pit-lane exit was still closed.

Raikkonen, who had entered the pits in third place, and Kubica stopped side by side at the red light, but Hamilton failed to notice in time that they had stopped, and he ploughed into the back of the Ferrari.

The incident broke the right-front suspension of Hamilton's car, putting him out of the race, and damaged the rear of Raikkonen's Ferrari sufficiently for him to be forced into retirement, too.

Hamilton said he had been told by the team that the red light was on at the end of the pit lane, but that the warning came "a little bit late".

The incident cost Hamilton the championship lead, which has now been assumed by Kubica.

The BMW driver, who has driven an impressively consistent season to deliver on promise that has been evident since he made his debut in 2006, is four points clear of Hamilton, who is tied on points with Massa.

Massa's race was ruined when he had to stop twice within a lap because of a breakdown in communication during the safety car period.

He queued behind Raikkonen, only to find that Ferrari could not refuel him, and he had to do another lap.

When he did come in, Ferrari chose to keep him on a two-stop strategy - like Kubica - but the ground he had already lost ensured he was out of contention for a top finish.

Hamilton's exit threw the race wide open, but Kubica always had the upper hand.

Heidfeld led as the safety car pulled off, ahead of eight other cars which did not stop during the caution period, and Kubica in 10th place.

Heidfeld quickly pulled out a huge lead over Barrichello's Honda in second place, and was able to rejoin still ahead of Kubica and fuelled to the end of the race when he made his one and only pit stop on lap 29.

But within two laps Kubica passed him into the first corner in what looked like a co-ordinated piece of team play as BMW Sauber tried to maximise their chances.

Kubica, hailed as a future world champion since he replaced Jacques Villeneuve at BMW Sauber mid-way through 2006, set about building enough of an advantage to enable him to make a second stop without losing the lead.

Heidfeld was left to fend off Fernando Alonso's Renault, which had run fifth from the start and, like Kubica, also needed to stop again.

The German did his job to perfection, and Alonso eventually spun coming out of turn seven on lap 46, possibly because of a glitch in his gearbox.

Kubica lost a lot of time behind Timo Glock's Toyota between laps 38 and 42, but he was more than able to pull out the advantage he needed in the seven laps before his final stop.

His win comes at the circuit where he suffered a huge accident only one year ago.

Results from the Canadian Grand Prix:

01 R. Kubica BMW 1:36:24.447
02 N. Heidfeld BMW + 16.495
03 D. Coulthard Red Bull + 23.352
04 T. Glock Toyota + 42.627
05 F. Massa Ferrari + 43.934
06 J. Trulli Toyota + 47.775
07 R. Barrichello Honda + 53.597
08 S. Vettel Scuderia Toro Rosso + 54.120
09 H. Kovalainen McLaren + 54.433
10 N. Rosberg Williams + 57.749
11 J. Button Honda + 1:17.540
12 M. Webber Red Bull + 1:21.229
13 S. Bourdais Scuderia Toro Rosso + 1 laps

Did not finish
14 G. Fisichella Force India F1 + 17 laps
15 K. Nakajima Williams + 23 laps
16 F. Alonso Renault + 25 laps
17 N. Piquet jr. Renault + 29 laps
18 K. Räikkönen Ferrari + 50 laps
19 L. Hamilton McLaren + 50 laps
20 A. Sutil Force India F1 + 56 laps