An electrical storm has made its force known early in the Malaysian Grand Prix, with bolts of lightning affecting course equipment and even briefly interrupting the television feed out of Sepang International Circuit.
Torrential rain has also flooded parts of the track, and forced race control to activate the safety car at the start of lap 7 of the race. Two laps later, and with forecasts that the downpour could last another 30 minutes before abating, race director Charlie Whiting opted to terminate track activity for the duration and brought out the red flag instead.
At the time the red flag came out, the running order saw Lewis Hamilton leading Jenson Button, Sergio Perez, Mark Webber, Fernando Alonso and Sebastian Vettel.
Jean-Eric Vergne was running in seventh ahead of Felipe Massa and Nico Rosberg, while HRT's Narain Karthikeyan found himself in a stunning tenth position - and in the points! - as a result of having gambled on full wets and not having had to pit before the red flag came out.
The race had started with half the track dry and half getting rapidly very wet, but the rapidly changing conditions had caught out many drivers including Michael Schumacher and Romain Grosjean, who spun in the poor conditions on the first lap after making contact. Both drivers continued, although Grosjean later spun out into retirement when the downpour properly picked up.
Lewis Hamilton had leapt into an early lead after Jenson Button backed out of a turn 1 challenge at the start. Button was later the first of the two McLaren drivers to join the general rush to pit lane for full wet tyres; when Hamilton followed suit next time around he only just managed to rejoin the track ahead of his team mate.
The race still needs to reach half distance (29 laps) before full championship points are awarded. There is a four hour window to get the race completed before it would have to be called off, as last happened in Malaysia in 2009.
With the rain abating, the estimated time for the race to restart has been given as 10.15am BST.