In the dark before dawn, social workers advance slowly down a narrow road dividing two vast slums, entering a landscape of littered streets and broken-down shacks, where an open-air crack cocaine market does business among piles of rubble.
Escorted by police through this "cracolandia", or crackland, they look behind cardboard lean-tos, in corners hidden by overgrown weeds for drug users who emerge, dazed, from ragged blankets. Some fight and run. One frantic young woman, her pregnant belly bulging under her short top, starts crying and pulling at her hair as police officers securing the area try to pacify her.
"Calm down, Taiane. Calm down," says an officer who knows her. "Look at me. It's me."
About two decades after the United States emerged from the worst of its own crack epidemic, Brazilian authorities are watching the cheap drug spread across the country of 190 million people. They have far fewer resources to deal with it, despite a booming economy that expanded 7.5 per cent last year.
No corner of Brazil has been spared. A recent survey by the National Federation of Counties found 98 per cent of them had registered traffic or consumption of crack, which is cocaine that has been processed so it can be smoked.
In Sao Paulo, the first place in Brazil to have a large consumer market for the drug beginning in the 1990s, seizures of crack went from 595kg in 2006 to 1636kg in 2009, federal police say. In Rio de Janeiro, arrests related to crack jumped from 546 in 2009 to 2597 in 2010, according to the research arm of the city's public safety department.
This spike happened even as consumption of the drug started to dwindle in the US. According to the United Nations' World Drug Report 2011, a squeeze on supplies from Mexico drove prices up by more than 80 per cent between 2006 and 2009.
Meanwhile, Brazil became the main transit country for cocaine streaming from the producing Andean nations to Europe. With a growing economy after years of hyperinflation, Brazilians also had more cash to spend on drugs.
Soon, more crack was being seized in Brazil than in the US. The UN report indicates 163kg was seized in the US in 2009, only 10 per cent of what Brazilian police say they seized in Sao Paulo alone in the same year.
"For us doctors, there is a crack epidemic," said Ricardo Paiva, who monitors the spread of the drug for the National Council of Medicine, a group representing doctors. "We feel we're losing the war."
It's a deadly battle. Research by the Federal University of Sao Paulo showed that after five years, one-third of crack users had died, most of them from violence.
A federal Government plan to fight the drug was signed in May 2010, with a budget of US$253 million ($295 million). Critics said from the beginning the resources were not nearly enough. A year later, implementation was lagging. Of the funds budgeted, only US$57 million had been allocated, and of that, only US$3 million was spent.
"It's been just talk," said Paiva. "This is a serious public health problem, and the Government cannot be absent."
Calls and emails to the Federal Department of Drug Control, under the Justice Ministry, were not returned.
In a recent deposition before Congress, Pedro Delgado, the Health Ministry's co-ordinator for mental health, drug and alcohol abuse, said Brazil had about 600,000 crack users.
Crack was cheap enough, at US$3 a rock, to reach street children and the unemployed, Delgado told the representatives.
In a sweep of the cracolandia between the Manguinhos slum and the Mandela complex of shantytowns in Rio, 58 users who had been living in the streets were picked up.
Ten were teenagers or children. At least three women were far along in pregnancy. They had little schooling, scant or no access to healthcare and no contact with the social programmes that could have helped them.
Sitting in the sun a few metres away from the pile of drugs and weapons seized in the raid, Pricila Nascimento ate her fill of crackers washed down with soda. Only 17, she bore the marks of four years spent on the streets: missing teeth, a couple of long scars on her legs. She toyed with her hairclips as she spoke.
One of eight children, she studied until fifth grade, then left home. On the streets, she met young men who introduced her to crack, at first mixed with marijuana or tobacco, then straight. She lost track of her parents long ago.
"My mother always taught me to take care of myself," she said. She begs for money, and steals. "I tell you, I don't go hungry."
Until March, minors like Nascimento were picked up by police then released back to the streets, where a girl will prostitute herself just to inhale smoke from a man's pipe, according to Valeria Aragao, head of the police's juvenile section.
Aragao and Rodrigo Bethlem, the city's head of social welfare, teamed up with police in a pilot programme aimed at changing the violence-prone life, at least for minors.
"When parents can't take care of their children, their welfare is everyone's responsibility," Aragao said. "We have to guarantee their right to dignity and life."
The children and teenagers picked up since May 31 are being returned to their families or forced into shelters especially set up to detox them with medical support.
Four centres with 145 beds in all are set aside for the programme, and 40 more are planned. The adults are offered treatment, but are not forced into a shelter.
Walter Maierovitch, a former drug tsar, proposes programmes that offer adults health services and a safe place to use drugs. "Insisting on programmes that demand abstinence doesn't work," he said. "The Government can't just sweep people up."
Bethlem says there has been "a real abandonment, an absence of the state" in dealing with the crisis. His fear is that Rio's crackland will become a fixture like Sao Paulo's.
"We can't start to think this is common, acceptable, to have people living like this," he said.
In the heart of Sao Paulo, an area roughly 10 blocks by 10 blocks, is the oldest example of Brazil's crack problem. Addicts gather in groups of hundreds or break off into smaller bands, smoking rocks.
On a recent evening, a 23-year-old man calling himself Mario lay on a sidewalk, naked under a ragged blanket. He took a hit on his homemade pipe and apologised for how he smelled. "I soiled myself, but I can't get clean," he said.
Mario, a paraplegic, lifts his blanket to reveal two shrunken legs. His wheelchair was stolen while he slept, so he cannot get anywhere to bathe.
In Rio, even the briefest look into the lives of the crack-addicted kids reveals the magnitude of the challenge ahead.
A skinny, restless teenager, Junior Gomes de Santos looks smaller and younger than his 14 years. His eyes are yellow and bloodshot; he grinds his teeth as he talks, looking down and away.
He left home because his father beat him. A cousin introduced him to crack - he doesn't remember when. He can write his name, but little more. He knows he'll be taken to a shelter, but won't stay.
"I'm going to eat, drink and bolt, go back to where I was," he said. Yes, he knows it's dangerous on the streets, he said, but he doesn't care.
"From this world, I'm not going to take anything," he said, looking up, flashing a brief, eerie grin. "Just a coffin as a souvenir."
600,000 Crack users in Brazil, according to Government statistics
595kg Of crack seized in Sao Paulo in 200
1636kg Of the drug seized in 2009
546 Crack-related arrests in Rio de Janeiro in 2009
2597 Crack-related arrests in the city last year
33% Of crack users died within five years of using the drug, according to Brazilian research.