Two of F1's leading team principals have sprung to the defence of Brazilian Grand Prix organisers following the attempted armed ambush on reigning F1 World Champion Jenson Button last weekend - arguing that there is 'a limit' regarding what they can do to ensure competitors' safety and insisting they are confident that 'the maximum' is being done to improve the situation.

Brazil has been under fire ever since McLaren-Mercedes star Button and his father, manager and trainer were the victims of a failed carjacking after leaving the Interlagos circuit to return to their hotel in S?o Paulo on Saturday evening after qualifying.

The quartet were approached by up to six gun-wielding assailants as they were stuck in stationary traffic in a favela (shanty town), whilst in separate incidents, three Sauber engineers were robbed at gunpoint and a group of Formula One Management (FOM) employees were similarly targeted after they stopped at the roadside to change a tyre.

Button's former team-mate and current Williams ace Rubens Barrichello has lamented the attacks as an 'embarrassment' for his country [see separate story - click here] - and many have demanded that Interlagos' spot on the annual F1 calendar be called into review due to an unacceptable level of danger.

Whilst acknowledging that the violent criminal element in S?o Paulo - an issue that seems to be getting worse from year-to-year - is one that needs seriously addressing especially in the light of major upcoming international sporting events in Brazil, McLaren's Martin Whitmarsh and Ferrari counterpart Stefano Domenicali have urged that blame should not be attached to the grand prix's organisers, and that nor should the unsavoury series of events be allowed to detract from what is invariably a warm welcome and superb on-track spectacle at the Aut?dromo Jos? Carlos Pace.

"In fairness to the organisers, I don't think they can be responsible for what goes on there," underlined Button's boss Whitmarsh, quoted by ITV-F1. "There's a limit to what the organisers can do. We've heard about [the problem] over the years and it's clearly escalated - when they start carrying sub-machine guns, then it starts to take on a slightly bigger level.

"That's worrying, but they've got a soccer world cup and an Olympics coming so I think it's something they'll have to work quite hard on in this country - and I'm sure they will. This country is on an economic bubble at the moment, so it would be nice to see it develop as I'm sure it will do in the coming years."

"I heard about these things and to be honest I don't want to say it is a dangerous situation here," added Domenicali, echoing the assertion of the sport's commercial rights-holder Bernie Ecclestone [see separate story - click here]. "We know that everywhere in the world that can happen. I think we need to thank the organisers, who are trying to do the maximum that they can.

"I would like to stress this positive point, because I know this weekend there were some problems, but we didn't take any extra precautions - we tried to do normal stuff. I want to stress the fact that in Brazil the atmosphere is really great."