24-hour CCTV cameras installed in a Rio favela Rocinha, Rio's biggest favela, is being watched since Tuesday by 80 surveillance cameras operating 24 hours a day - making it one of the best watched places in the world, according to the police. A year after the 'pacification' of the favela by the army and the police, and the expulsion of the drug traffickers, these CCTV cameras have been put in 12 strategic places, as part of the city's efforts to clean up its reputation for crime, with a year to go before the World Cup. Images and soundbites.