Gangs bring anarchy to Brazil's biggest city

The violence that terrorised Sao Paulo, Brazil's most populous state, in recent months has returned, with powerful criminal gangs setting fire to courthouses, incinerating buses, attacking banks and throwing homemade bombs at police stations.

In three nights of uproar that have seen large areas of the financial capital, Sao Paulo city, set ablaze, police have killed at least half a dozen suspects, while gang members have attacked hundreds of targets throughout Sao Paulo state.