caveirão カヴェイラン
An armored personnel carrier in service of the Special Operations Battalion of the police of Rio de Janeiro, Brazil. The "Caveirão":http://pt.wikipedia.org/wiki/Caveir%C3%A3o, whose name literally means "big skull", comes from its operator's symbol: a skull and a knife.

It is a black vehicle similar to a big van with a static turret-like superstructure. Despite its threatening appearance, it carries no weapons. Its purpose is solely to safely transport policemen to and from high-intensity urban conflicts.
caveirao