Rio de Janeiro, Brazil - Under a footbridge, when night falls and it's pitch black, the only light that emanates is from flames given off from a few cigarette lighters and a couple candles.
On the dirt floor trash is scattered about, including condoms and plastic water cups with holes punched in the bottom to be used as rudimentary pipes; the pungent stench of urine hangs in the air.
It's filthy, but nobody seems to notice. The couple dozen people here on the ground are all too fixated on taking their next hit of crack cocaine.
This scene plays out inside the Antares slum - or favela as it is known in Brazil - in the industrial outskirts of Rio de Janeiro.
There are men, women, and even children, all using.
Paulo, a middle-aged man and father of three young children, is hunched over and inhaling a hit.
"I use crack every day, almost every hour," he said without hesitation. "This is a drug you fall in love with the first time you use it."
The Antares favela is under the command of dozens of machine gun wielding young men from a faction of the Comando Vermelho drug gang.
It's generally considered a no-go area for police.
A night-time visit inside the drug den in the slum reveals a troubling scene but points to a larger picture of how crack has become a security and public health epidemic in Brazil, spreading to all corners of the country and infiltrating all economic classes.
But since a rock of crack can be purchased for only R$5 (less than $3 USD), the most desperate and downtrodden users tend to congregate by the hundreds in and around Rio's favelas, where it can be easily purchased.
That is partially why, in an unprecedented move, some drug traffickers have unilaterally decided to stop selling crack in the favelas they control.
In both Mandela and Jacarezinho favelas - combined home to more than 100,000 residents - crack can no longer be purchased. Two drug bosses, who control each favela, gave the orders to halt sales.
A dirt road bordering Mandela favela that previously was known to be one of Rio's largest concentrations of users (known as "cracolanidias" in Brazil) is where hundreds of users and sellers would congregate day and night.
The road is now clear of any signs of users or sellers.
"I am not going to lie to you, there is a lot of profit to be made on crack," said Rodrigo, a top trafficker in Mandela who used to manage all the crack operations, told Al Jazeera. He asked that his real name not be used. "But crack also brought destruction in our community as well, so we're not selling it anymore. Addicts were robbing homes, killing each other for nothing inside the community. We wanted to avoid all that, so we stopped selling it."
The traffickers in Mandela, like Rodrigo, readily admit they still sell marijuana and powder cocaine and were happy to show it to Al Jazeera. Business was good for those drugs; bags of money sat out on tables at sales points in the slum.
But those other drugs, they said, don't seem to cause the same social problems in the favelas they control.
Crack sales have been halted in just two of Rio's favelas, but Flavia Pinheiro Froes, a lawyer who represents many drug traffickers, said she expects more drug bosses to join in soon.
Pinheiro Froes heads "Anjos da Liberdade" (Angels of Liberty), an organisation that provides job training for former drug dealers in Rio. Her clients include top traffickers from all three of Rio's main trafficking organisations: Comando Vermelho, Amigos dos Amigos and Terceiro Comando Puro.
|Flavia Pinheiro Froes, a lawyer to some of Rio's biggest drug traffickers, says many of the drug bosses want to stop selling crack [Gabriel Elizondo/Al Jazeera]
Her efforts were behind halting sales at Mandela and Jacarezinho favelas, and now she is using her contacts with the powerful gang leaders from all sides to convince even more to stop selling crack.
"Our campaign is not only done in the communities directly with the traffickers that are selling, but also with some of the drug gang leaders that are in jail," Pinheiro Froes said. "I think convincing the seller could be one of the most efficient ways to combat crack because if there is no supply we will be able to solve the problem of the consumer."
Pinheiro Froes, whose current and past clients make up a "most wanted" list of Rio's most notorious drug traffickers, said many traffickers witness the destruction crack wreaks on lives first hand as they have family and friends who are addicted.
She said she is hoping for even commitments for the gangs to stop buying from the big suppliers, some of whom are in neighbouring countries.
Police in Rio remain sceptical and dismissive of any gestures by the traffickers, even those who have already stopped selling crack.
Marcello Maia, one of the Rio civil police's top drug crime investigators, believes the move is just an attempt by the traffickers to gain sympathy and divert attention from the other drugs they readily admit them continue to sell.
"I think this is just a trick that the traffickers are doing," Maia told Al Jazeera. "What they think is that now the police will stop combating other drugs they are selling, and we still stop entering their strongholds. But this is not what is going to happen."
For police and city and federal officials, curtailing crack addiction is a new, major national priority.
Last November, President Dilma Rousseff launched a two-year, $2bn nationwide campaign to get crack addicts off the streets, and to bolster capacity of treatment facilities. More than $125m of that money will go directly to Rio de Janeiro, local officials have said.
But the scale of the problem is immense and was easily observable on a trip that accompanied some of Rio's social service officials on a recent morning operation to get addicts off the streets.
Some of the users were children too, stoned to even stand up, and had to be carried to waiting vans.
Security is also a risk, as social service officials can only safely reach some of the crack dens bordering the city slums with protection of special forces police.
On the operation seen by Al Jazeera, two dozen social assistance officers took 87 crack users - 16 of which were children - off the streets of Rio and into treatment centres in the matter of four hours.
So far this year, there have been more than 30 such interdiction operations by the city.
But once addicts are admitted into assistance centres, there is no law forcing adults to stay; they are free to walk out whenever they please, and many do after getting a hot shower and a meal.
The money set aside from the federal government is meant to add more officers and treatment centres all over Brazil to try to give officials more leverage to deal with the problem.
Future of crack sales
Back at Antares favela, crack addicts are everywhere, scurrying through the darkness to find a corner to smoke, while crack sales continue unabated.
One trafficker, "Joao", said they are prepared to stop sales if told to.
"If our boss tells us to stop selling crack, we will," Joao said.
Talk like that gives hope to people like Pinheiro Froes, the lawyer, who said she is hoping to get commitments from leaders of all three of Rio's main drug gangs to halt sales in all of Rio's slums by the end of this year.
But the disturbing peek inside the dark underworld of a crack den at Antares favela at night, perhaps also a reminder that for all the efforts to drive crack from the slums, those looking for a quick fix might always be able to find it somewhere.
Follow Gabriel Elizondo on Twitter @elizondogabriel
- With producing by Alan Roberto Lima and Maria Elena Romero.