Highlights - Hamilton wins in Belgium
Lewis Hamilton won the Belgian Grand Prix after an incident-packed race at Spa-Francorchamps.
The McLaren Mercedes driver retook the lead in the World Championship with an almost error-free drive, leading from the first corner to the finish.
Red Bull's Mark Webber was second, with Renault's Robert Kubica third, and Ferrari's Felipe Massa fourth.
Jenson Button and Fernando Alonso crashed out, and Sebastian Vettel failed to score a point.
Force India's Adrian Sutil was fifth, with Nico Rosberg sixth for Mercedes.
Rosberg's team-mate Michael Schumacher finished seventh after starting 21st, Kamui Kobayashi eighth for Sauber, Renault's Vitaly Petrov ninth and Force India's Tonio Liuzzi tenth after Toro Rosso's Jaime Alguersuari, who crossed the line ahead of Liuzzi, was handed a post-race 20 second penalty.
"I'm ecstatic, it was a great weekend," said Hamilton, whose driving was praised by his team principal Martin Whitmarsh. "A race like that can be a lottery, so I'm so happy and grateful to come out on top."
With the drivers having been clearly warned they would be punished if they used the run-off at the opening corner, La Source, to gain any kind of advantage on the first lap, the likelihood of collisions appeared to be increased.
What was not predicted was that pole-sitter Webber would make an appalling start, to such an extent that he reached the corner in sixth.
As Hamilton pulled ahead, Kubica weaved around the Australian, and just managed to hold off the charging Button, but rain was already beginning to fall.
By the time the field got to the Bus Stop chicane, the track was damp enough for at least nine cars to have to use the run-off area. Rubens Barrichello, in his 300th Grand Prix, was the big loser, running hard into the back of Fernando Alonso's Ferrari, a collision which put him out of the race.
With the safety car out the choice was now whether to switch to intermediates or stay on slicks, and most, including the leaders chose to stay on their smooth rubber.
It proved to be the right choice as the the rain immediately eased off and as Hamilton stretched his lead after the safety car recalled after two laps, Button and Vettel passed Kubica, while Alonso began the long climb through the field after pitting for fresh slicks.
Button had picked up some minor front-wing damage as he fought with Kubica into the first corner and struggled with the balance of his car, but while he could not live with the speed of team-mate Hamilton, the world champion had enough in hand to keep Vettel at bay.
By lap 15, Hamilton had 11 seconds in hand but at the end of the next, the rain came again and indirectly caused disaster for Button as Vettel, with a run on the Briton, lost control under braking on the damp track and speared into the side of the McLaren.
Incredibly, Vettel was able to recover just in time to steer his Red Bull across the track and into the pit lane, from where he rejoined the race after a quick front wing change.
Belgian Grand Prix - Top three drivers
Button, on the other hand, was unable to continue and having been in no way at fault, was entitled to be furious.
"All I felt was a really big bang in the sidepod and I lost drive immediately, I don't know what he was playing at really. From the point of view of the championship, it's a massive blow," he said.
The stewards immediately announced the incident would be investigated, and Vettel was handed a drive through penalty for causing an avoidable collision.
The incident left Hamilton clear of Kubica, Webber, Felipe Massa, Adrian Sutil, and remarkably, Schumacher, who had started 21st.
At the half-way point, Sutil was the first of the leading pack to change his slick tyres followed by Webber, who was trying to get the jump on Kubica. Vettel, meanwhile, was down in 14th after serving his penalty, but lapping more quickly than any other driver.
Hamilton stopped two laps later, and while the track stayed dry, it was looking good for the Briton. Behind him, poetic justice awaited Vettel while attempting to pass Tonio Liuzzi for 11th, as the German sliced open a tyre on the Italian's front wing. Once again, he was able to limp back to the pitlane, but he rejoined in 20th.
At the three-quarter point Hamilton was maintaining a comfortable 10-second gap to Kubica, but rain was clearly on its way. As it began falling, Hamilton and Webber stayed out - and Hamilton could not stay on the damp track at Rivage.
Somehow he kept his car out of the barriers, and was back on track before Webber could capitalise. Immediately Hamilton came in to switch to intermediates. Webber did likewise, as did Kubica - but the Pole overshot his pitlane box, a mistake that enabled Webber to come out in second.
There was more drama to come, however. On lap 39, Alonso spun out at the exit to Les Combes, leaving the Ferrari in the middle of the track, necessitating another safety car period.
Feeling the grip levels carefully, Hamilton nailed the restart to keep Webber at bay. The inevitable concertina effect behind him ensured plenty of incident in the closing laps, but Hamilton maintained his concentration in superb style to score a potentially crucial victory.