Brazil is the host for the FIFA World Cup next year and the Summer Olympics in 2016. Analysts say the country's unremitting crime waves have thrown a pall on pre-games tourism.
Critics of President Dilma Rousseff want the government to do more to counter multiple threats from organized crime gangs controlling narcotics, prostitution and protection rackets.
Critics say a perceived weakening of the state and government agencies through a rash of press exposures of political corruption has hindered law enforcement in Brazil.
Organized criminals acting from within the penitentiaries targeted the country's rich, corporations, public infrastructure and impoverished dwellers of favelas, slums that remain a key feature of Brazil's urban life.
Santa Catarina attracts international tourists to its beaches and whale sanctuaries. It is also a major hub for drug traffickers profiting from both locals and foreign visitors.
Opposition critics cite police corruption but are cautious themselves over the risk of causing offense with criticism in legal and illegal power centers of the region.
The fact that prisoners can orchestrate a street riot points to a major problem, say critics.
In the latest flare-up criminal gangs in the country's prisons ordered hired help to set fire to buses and automobiles in a reign of terror that left damage and casualties in about 30 urban centers, including the state capital Florianopolis.
Most of the unrest was rooted in inmates' campaign for better prison conditions but officials didn't rule out gang wars.
Military police officials said their counteroffensive, called Operation Secure Santa Catarina, was going well as help from federal police arrived.
They recognized that street security was a high-profile issue as Brazil gears up for the 2014 World Cup and the 2016 Summer Olympics in Rio de Janeiro, they said. Events related to both games are likely to spread to other locations.
Authorities reported many arrests and transfers of suspects between prisons in an effort to defuse tensions. Neither the number of arrests nor the extent of casualties was immediately confirmed. Lawyers acting for crime gangs were among those detained.
It was the second major outbreak of violence in Santa Catarina, which witnessed unrest in November last year.
Santa Catarina touts itself as one of the liveliest cities in Brazil with a superior quality of life. Critics say the city's attributes are blighted by high crime and extreme income disparities.
The city's 6.2 million inhabitants include students at the city's academic institutions, including the Federal University of Santa Catarina, often ranked as the fourth best overall university in Latin America after Sao Paolo and Campinas in Brazil and Pontifical Catholic University of Chile.
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