A nervous F1 circus has travelled to Sao Paulo for F1's 2012 finale, amid reports of more than 1000 murders in the Brazilian city this year.
Britain's Guardian said the worse-than-usual bloodshed is due to drug-linked organised crime.
"We are not staying in gangland, though the track is near there," a team boss is quoted as saying. "But we don't go out in team colours."
Jenson Button, who two years ago was the victim of an attempted armed attack in Sao Paulo, admitted this week: "We are having armoured vehicles and a police escort."
According to the Times newspaper, the US state department is describing the Sao Paulo violence as "critical" and has warned against gangs targeting foreigners.
Gangs aside, the F1 world - and title protagonists Sebastian Vettel and Fernando Alonso in particular - have their eyes on the weather forecast.
The leading Brazilian authority Climatempo is predicting "intense rain" for qualifying and the race.
With Ferrari's Alonso hoping desperately for rain in order to pull back the dominance of Vettel's Red Bull, Dr Helmut Marko insisted: "Sebastian is also an excellent rain driver."
McLaren's Button commented: "There is a massive chance that it could be chucking it down. It (the title) is definitely not done."