In Salvador, the northeastern city where police protests unleashed a wave of bloodshed and chaos early this month, celebrants raced to buy tickets and costumes that had gone unsold during the disorder. In Rio de Janeiro, where a recent strike was peaceful despite fears of similar unrest, merrymakers prepared for the hundreds of parades and block parties that pulsate across the city's lush landscape each year.

The prospect for normal festivities is a welcome relief to locals, authorities, and businesses in two of Brazil's most visited cities. In addition to disrupting the high point of the annual tourism agenda, the troubles heightened longstanding doubts about security and overall preparedness in a country selected to host the 2014 soccer World Cup and 2016 Summer Olympics.

Those in Brazil for carnival said they saw few signs that fallout from the police strikes would overshadow the revelry.

"Carnival is sheer joy," said Mark Evans, a 32-year-old tourist from Los Angeles, California. Strolling along the black-and-white tilework of Rio's Copacabana waterfront, Evans and his Colombian girlfriend said they planned to enjoy the Salvador festivities, too.

Carnival, whose roots lie in last-minute carousal before the austere Catholic season of Lent, officially begins in Brazil on Friday and lasts through early Wednesday.

A strike by police for higher pay earlier this month unleashed a crime spree in Salvador, Brazil's third-largest city, that led to more than 150 murders in a 12-day period, over twice the regular homicide rate. Looting, assaults, and vandalism prompted residents to stay home, shopkeepers to close doors, and many would-be visitors to cancel their plans.

Brazil's government deployed more than 4,000 army troops to Salvador to restore order and prepared to send many more to Rio when police there launched a similar strike last week. Because only a small fraction of Rio's police actually took part in the protest, however, few problems ensued during the walkout.

Carnival each year attracts as many as 250,000 foreign tourists to Rio and twice that number to Salvador. Along with millions of local revellers, the visitors spend over half a billion dollars in Rio and more than $300 million in Salvador, according to local authorities.

While Salvador's party is marked by massive carnival floats that wend their way along its seaside avenues, the official parades in Rio take place in a stadium-like corridor built just for the occasion. Tickets for the parades can cost hundreds of dollars or more, and big corporations, especially Brazilian beermakers, hire celebrities to preside over flashy parties in skyboxes above the processions.

Playboy founder Hugh Hefner and entertainer Jennifer Lopez are scheduled to be among the draws this year.

In recent years, the big business around the event in Rio has led to a push by grass-roots organizations to take the party back to the street. Massive block parties, or blocos, now steal much of the thunder from the official production.

The blocos have colourful names like "Christ's Armpit," "Fire In Your Underpants" and "I'll Leave My Woman, But Not My Beer," and attract thousands of loyal followers who parade for hours at a time through Rio's streets to the beat of samba.

(Writing by Paulo Prada; Editing by Todd Benson and Paul Simao)

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