Robert Kubica claimed his maiden victory and took control of the world drivers' championship as Lewis Hamilton's Canadian Grand Prix ended in disaster in Montreal.

Pole Kubica survived a horrendous crash at Circuit Gilles Villeneuve 12 months ago and the BMW Sauber driver took full advantage of a pit-lane accident that took out McLaren's world championship leader Hamilton and world champion Kimi Raikkonen of Ferrari.

Hamilton crashed into the back of Raikkonen as they emerged from a pit stop on lap 18 with the Englishman failing to spot the red light at the end of the lane as the Ferrari was waiting on the line.

It was a BMW Sauber one-two as Nick Heidfeld claimed the runners-up spot for the second year in a row.

The drama also cleared the way for Scotland's David Coulthard to score his first points of the season with an invaluable third-place finish to ease the pressure on his seat at Red Bull Racing.

Hamilton, who had claimed his maiden win in Canada last year, had been in control until his disastrous exit, setting a really quick pace to build a 4.3 second lead over Kubica after the first 10 laps following a series of fastest laps for the Englishman.

A spin-out by Force India's Adrian Sutil set in motion the chain of events which led to Hamilton and Raikkonen's pit-lane shunt.

Sutil ground to a halt which caused the yellow flags to come out as his car's brakes looked to have overheated and smoke began to plume from Force India.

The safety car soon followed to undo Hamilton's six-second lead and when the pit lane opened, all the leading contenders came in for their first fuel stops at the end of lap 18.

It was a bad pit stop for Hamilton as both Raikkonen and Kubica came out first and vied for the lead only to be stopped by a red light at the end of the pit lane.

They came to a halt side by side but Hamilton careered into the back of the Ferrari, forcing them both out of the race. Rosberg went into the back of Hamilton but managed to continue racing.

As both drivers got out of their cars, Raikkonen theatrically pointed out the pit signals to Hamilton to indicate they had been on red and the McLaren man had no excuse. He was clearly furious with himself as he returned to the McLaren garage and waved away following TV cameras.

Hamilton, speaking to reporters as the race continued without him, said: "I saw the two guys in front of me battling in the pit lane and all of a sudden they stopped.

"I saw the red light but it was too late to stop.

"I don't think it's a racing incident. It's unfortunate and I apologise to Kimi if I ruined his race.

"I would rather we were both still in the race."

The drama left BMW's Heidfeld in the lead with Rubens Barrichello's Honda in second and the Williams of Kazuki Nakajima in third as the race resumed without the safety car.

Of the drivers that had pitted, Kubica was 10th, with Alonso 11th and his Renault team-mate Nelson Piquet 12th with McLaren's Heikki Kovalainen 13th.

With a potential third place on the cards, Piquet lost the back end of his Renault going into a corner and nearly took out Felipe Massa's Ferrari as he reversed onto the track.

It marked another error for the Brazilian in a so-far terrible rookie season.

Piquet's problems came to a head as he retired and his team-mate Alonso's difficulties continued when he spun out on the newly-resurfaced Turn 7, which did not seem to be holding up in race conditions.

Alonso hit the wall but blamed gearbox problems as he went out and there was yet more drama as Nakajima went out in another pit lane accident, crashing into the wall for the sixth retirement of the race after running over his loose nosecone.

Kubica was leading a BMW Sauber one-two with Heidfeld a distant second, allowing him to make a second pit stop and maintain a first place he was never close to relinquishing.

Toyota's Timo Glock came fourth for his first points, with Massa fifth to give Ferrari some consolation and Jarno Trulli, also of Toyota, sixth.

But the day belonged to BMW Sauber, who moved above McLaren into second place in the constructors' championship behind Ferrari, and particularly to Kubica.

Afterwards Kubica thanked the team that gave him his first start in Formula One when they signed him as their official Friday test driver at the start of their first season with BMW on board in 2006.

"It's very fantastic to win my first race for BMW Sauber, which I joined from the beginning. We grew up together and thanks to the team for providing me with the car.

"We managed first and second and we were right there in this race.

"At first I couldn't hold Lewis' pace but it was a fantastic race, for the team, for me, for my country and thanks for the fans here in Canada."

Kubica was in an ideal position to see Raikkonen's demise at the hands of Hamilton.

"We all pitted together and the red light was still on at the end of the pit lane," he said. "I saw Kimi side by side with me.

"Then I just heard a big shunt and saw Kimi's moving and realised it was Lewis. He was over Kimi's rear wing.

"I just kept concentrating waited for the green light and managed to pull away well."

Kubica said the most difficult part of his victory had been building up a lead over Heidfeld large enough to protect when he made his second pit stop.

"I had seven or eight laps to make a 16 or 17-second margin in order to come out of the pits in front of Nick.

"I never struggled so much, I was pushing so much to do it and I managed to do it so it was a great race.

"Then it was just a question of bringing the BMW home.

"The last laps were very, very difficult. The team was telling me to stay calm and not push too much but I wasn't pushing for 10 or 15 laps, it was just amazing."