The future of the Brazilian Grand Prix at Sao Paulo's Interlagos circuit is this week clouded with uncertainty following the attempt by armed robbers to hijack the bullet-proof Mercedes limousine in which McLaren driver Jenson Button was travelling.

Jenson was being driven by an armed police driver who had been specially trained in defensive driving techniques. Also in the car were Jenson's father John, his manager Richard Goddard and his trainer Mike Collier. They stopped in a queue of cars at a set of traffic lights on the main road outside the Interlagos track  when the potential assailants emerged from the shadows.

The driver made good his escape, ramming several other cars as he energetically cleared a path through the tightly packed traffic to get his VIP cargo back to the hotel in one piece. Button described him as "brilliant, a legend."

However, with attacks on Force India and Formula One Management personnel also taking place over the race weekend many were asking how long the epic Sao Paulo track could survive on the Championship schedule, only justified by the fact it is the sole F1 event in South America.

"Interlagos is 70 years old," Bernie Ecclestone said in the Brazilian GP programme. "A great deal of work has been done in the past few years to modernise it, but now we have reached a stage where parts of it would have to be demolished and built anew, such as the garage/pit complex."