The threat to Lewis Hamilton's world championship march came from Scuderia Toro Rosso boss Franz Tost, it has been revealed, after the Austrian alerted the authorities to potentially damaging video footage.

Although not caught by the official cameras at Fuji, Hamilton's antics behind the safety car were recorded by enthusiastic fans and, as is becoming increasingly common in this technology-led age, posted on the video sharing website YouTube. Made aware of the images, Tost alerted the FIA, which launched a investigation into Hamilton's tactics with the threat that the Briton could be docked points for causing the accident between STR's Sebastian Vettel and Red Bull Racing's Mark Webber.
The footage, apparently taken using a mobile 'phone, shows Hamilton moving wide to the right in a left-hand turn, with Webber having to slow to avoid passing the McLaren. Vettel later admitted that his focus had been taken by the leader before he slammed into the back of the RBR car.

Hamilton was seen to be accelerating and braking hard during both safety car periods in the Japanese Grand Prix, almost forcing Mclaren team-mate Fernando Alonso to pass him as the field lined up for the initial 'start', and then again as he prepared to keep Webber and Vettel behind him at the restart necessitated by Alonso's mid-race shunt. The F1 rulebook says that drivers must keep 'no more than five car lengths' between themselves and the car in front - in Hamilton's case, the safety car' - but the leader complained that Webber was getting too close as he attempted to warm his tyres and brakes.

Tost, however, admitted that he decided to make his protest after rookie Vettel was slapped with a ten-place grid penalty for this weekend's Chinese Grand Prix after being deemed culpable for the accident. Both the German and Webber complained that Hamilton's tactics had been distracting, with the Australian insisting that the Briton had done 'a sh*t job' during Thursday's press conference in Shanghai.

"You could see quite clearly that Hamilton slows down quite unexpectedly," Tost told Britain's Daily Telegraph newspaper, "Sebastian would have had to have gone between the cars [Webber and Hamilton] and there was no chance. It was totally unexpected. It looked like Hamilton was stopping, [and] that is why I went to the stewards."

If found guilty, Hamilton faces a maximum ten-point penalty or exclusion from this weekend's Chinese Grand Prix, conveniently extending the championship battle to Brazil later in the month, provided that his remaining challengers - Alonso and Ferrari's Kimi Raikkonen - take advantage. McLaren is expected to defend its driver's actions by using data to show that he needed to accelerate and brake as he did to ensure tyre and brake temperatures were at safe levels.