Button triumphs in stormy Sepang

The British driver, who had qualified in pole, was leading on the 33rd of 56 scheduled laps when the race was stopped after a thunderstorm broke at the Sepang International Circuit and - with the torrential rain refusing to relent and darkness descending on the track - organisers eventually decided not to restart the race, awarding half-points to the top eight finishers.

Nick Heidfeld benefited from a decision to run a heavy fuel load as he finished second for BMW Sauber while Timo Glock was third for Toyota after a strong run in intermediates during a period before the heavens fully opened.

Jarno Trulli was fourth in the second Toyota, with Brawn GP's Rubens Barrichello fifth and Mark Webber sixth for Red Bull.

World champion Lewis Hamilton was seventh for McLaren with Nico Rosberg eighth for Williams.

It was the first race to be red-flagged for rain since the 1991 Australian Grand Prix in Adelaide.

The rain finally arrived on lap 22, bringing most of the field in for a change to wet tyres and Hamilton was the biggest beneficiary as his first fuel stop helped to elevate his McLaren up to sixth place.

The Brawn had enjoyed little testing in wet conditions but Button showed his mastery of the conditions by opening up a 24.6-second lead over second-placed teammate Barrichello by lap 25, but Glock was flying in his Toyota, moving up through the field rapidly on intermediate tyres.

The rain intensified and Giancarlo Fisichella, Sebastian Vettel and Sebastien Buemi spun out in the treacherous conditions.

The safety car was deployed soon afterwards before the cars were red-flagged on lap 33 with Button leading from Glock in second and Heidfeld in third.