Felipe Dana / AP

A man smokes crack in the Manguinhos slum in Rio de Janeiro, Brazil, Aug. 7. Some drug bosses say they have stopped selling crack because it destabilizes their communities, making it harder to control areas long abandoned by the government. City authorities take credit for the change, arguing that drug gangs are trying to create a distraction and make police back off their offensive to take back the slums.

Business was brisk in the Mandela shantytown on a recent night. In the glow of a weak light bulb, customers pawed through packets of powdered cocaine and marijuana priced at $5, $10, $25. Teenage boys with semiautomatic weapons took in money and made change while flirting with girls in belly-baring tops lounging nearby.

Next to them, a gaggle of kids jumped on a trampoline, oblivious to the guns and drug-running that are part of everyday life in this and hundreds of other slums, known as favelas, across this metropolitan area of 12 million people. Conspicuously absent from the scene was crack, the most addictive and destructive drug in the triad that fuels Rio's lucrative narcotics trade.

-- Reported by the Associated Press

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Felipe Dana / AP

Traffickers and users gather at a drug selling point in the Antares slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

Traffickers sell drugs in the Antares slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

People gather in an area known as "Crackland" inside the Manguinhos slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

A trafficker test fires a riffle in the Mandela slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

Traffickers sell drugs in the Antares slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

A trafficker stands at a drug selling point that stopped selling crack in the Mandela slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

A masked and armed trafficker at a drug selling point that no longer sells crack in the Mandela slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

Crack users gather under a bridge in the Antares slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

A crack user leaves a crack house near the Manguinhos slum in Rio de Janeiro, Brazil.

Felipe Dana / AP

A Dancer of Porto da Pedra samba school parades on a float during carnival celebrations at the Sambadrome in Rio de Janeiro, Brazil, on Feb. 20, 2012.

Felipe Dana / AP

Dancers of Vila Isabel samba school parade at the Sambadrome on Feb. 20, 2012.

Felipe Dana / AP

A dancer from the Mocidade samba school parades on a float at the Sambadrome on Feb. 20, 2012.

Victor R. Caivano / AP

Revelers, some wearing costumes, cross a bridge as they arrive at the Sambadrome on Feb. 19, 2012.

Nacho Doce / Reuters

Children play as adults watch the Portela samba school parade at the Sambadrome on Feb. 19, 2012.

Silvia Izquierdo / AP

Performers from the Beija Flor samba school parade at the Sambadrome on Feb. 20, 2012.

Thousands of revelers gathered at the Sambadrome Sunday night for the crown jewel of Rio carnival as thirteen samba schools vied for a prize. Their elaborate floats, massive percussion sections and troupes of sequin and feather-clad dancers made their way down the avenue as spectators looked on from the bleachers.

Slideshow: Carnival celebrations

David Mercado / Reuters

From Rio de Janeiro to Venice revelers took to the streets in colorful costumes.

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On Saturday, a record-breaking 2.2 million people had attended the Cordao da Bola Preta parade, one of the city's oldest carnival street parties, the BBC reports.

The authorities see the five-day event as a crucial test for Rio's new central command center, which the city hopes will be a key to keeping order when it hosts 2014 soccer World Cup matches and the 2016 Olympics.

— The Associated Press contributed to this report.

• We kissed at carnival: Blog aids lost loves
• Brazil kicks off bigger, brighter carnival
• Just in time for carnival: Beginner's guide to Rio 

Victor R. Caivano / AP

A man sleeps on litter-filled stands at the end of the first day of carnival parades at the Sambadrome on Feb. 20, 2012.

Vanessa Carvalho / AFP - Getty Images

A reveler of Camisa Verde e Branco samba school sings and dances during the opening night of parades at the Sambadrome in Rio de Janeiro on Friday night.

Yasuyoshi Chiba / AFP - Getty Images

A reveler of Camisa Verde e Branco samba school waits before participating in the opening night of parades at the Sambadrome.

Vanessa Carvalho / AFP - Getty Images

A float of Camisa Verde e Branco samba school parades at the Sambadrome on Friday night.

Andre Penner / AP

A dancer performs during the Carnival parade on Friday night.

AP reports: The globe's biggest Carnival bash opens Friday, and it promises to be an even bigger blowout this year, with 20 percent more tourists expected than in 2011. Rio officials say they're also better prepared to keep the chaos under some semblance of control, with more portable toilets, traffic guards and paramedics, as well as a new central command center monitoring it all.

Vanessa Carvalho / AFP - Getty Images

Revelers of Camisa Verde e Branco samba school dance on Friday night.

"We want revelers to be conscious that they can party but also care for the city's public spaces," the president of Rio's tourism department, Antonio Figueira de Mello, said in a statement.

About 850,000 tourists are expected during the raucous, five-day free-for-all that kicks off when Rio's mayor hands the key to the city to rotund King Momo, the mythical jester figure who reigns over Carnival.

Andre Penner / AP

Drummers perform during the Carnival parade.

Related story:

• Previous photoBlogs about Carnival
• Just in time for Carnival: Beginner's guide to Rio

Photos by Victor R. Caivano / AP

A firefighter takes a dog downhill at the site of a mudslide to search for missing people in Jamapara, Brazil on Jan. 10, 2012.

Rescue personnel recover the body of a mudslide victim in Jamapara on Tuesday.

The Associated Press reports a mudslide caused by two days of rain has killed at least 13 people in a small town in southeastern Brazil, and another 11 are listed as missing, the head of the Rio de Janeiro state civil defense department said Tuesday.

Sergio Simoes told CBN radio that five bodies were pulled from beneath tons of mud and debris on Tuesday, bringing the death toll in the Jamapara district of Sapucaia city to 13. Eight bodies were found on Monday.

Antonio Marcos Silva dos Reis said he lost several friends in the mudslide. He said it "sounded like a huge explosion when it happened."

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