The number of foreign women detained for drug trafficking in Brazil in the past three years has soared. The BBC's Gary Duffy examines the increase and speaks to two British women who are currently in jail awaiting sentencing for smuggling cocaine.
British women warn against being drug mules
In a small room in Sao Paulo's main international airport, police officers rip open four books found in the suitcase of a Dutch passenger arrested while trying to board a flight to Europe.
Carefully concealed inside what appear to be academic texts, and wrapped in a variety of coverings, is 4kg of cocaine.
Brazil sits between other South American nations where the drug is widely produced, such as Colombia and Bolivia, and profitable markets for the drug dealers in Europe and South Africa.
Not surprisingly the country's airports receive a lot of unwelcome passengers.
Police at Guarulhos airport in Sao Paulo say several months ago they successfully disrupted a gang that was using cargo planes to smuggle drugs out the country.
There were more than 60 arrests, and the authorities say it seems to have forced drug traffickers to focus on alternatives such as using drug couriers.
There is no such thing as easy money, no such thing
In the past three years, the number of foreign women detained for drug trafficking has risen 253%.
This is starkly evident in Sao Paulo's Carandiru jail where, as well as the Brazilian inmates, there are more than 400 women from more than 60 countries.
Many risked their freedom for sums of money ranging from $3,000 to $13,000 (£2,000 to £8,000) - certainly less than what the drug traffickers controlling them can make.
'Just a nightmare'
Among the newest prisoners are Sasha Brooks and Kimberley Anderson, both 20 and from Nottingham in England. They have been friends for 15 years.
They were caught this year at Guarulhos airport with 5kg of cocaine. Sasha says they were foolish to get involved.
Located near cocaine-producing nations, Brazil is a popular transit route
"I was in debt, I needed money," she told BBC News, although for her own safety she is vague about how exactly she got involved.
"I just come across some guys that happened to do this kind of thing, and was kind of persuaded and told everything would be alright, and you just agree to do it."
Instead of solving her financial problems, she now faces the challenge of everyday life in a prison in the heart of Sao Paulo.
"People can take advantage because I don't know how to speak Portuguese fluently," she says.
"So that is very harsh - when you have problems in a prison - you can't back yourself up. Having four people in a cell, two of which sleep on a floor - it's just a nightmare."
Kimberley says they want others who may be thinking of doing the same thing to know what the consequences can be.
"No amount of money in the world can replace, give you back your freedom, your family, love. Because here, you don't have love - you understand?" Kimberley says.
"You don't have freedom, you don't have anything. To do this is not easy. Any amount of money, no matter what money you get told you'd be given to do this - don't! It is not worth it - no amount of money can give you back what you lose."
Sasha quietly agrees: "There is no such thing as easy money, no such thing."
Mario Menin, the police chief at the airport where the two were arrested, says most of those who are caught are simply being exploited.
"Usually the people carrying the drugs are less well off," he says.
At that moment I was so desperate about the money, and to do something for my life
"They have money problems, and the drug dealers use these people, and promise them a big advantage or reward, and get these people to take the drugs out of the country."
Some of the women in jail here have taken bigger risks.
Traffickers have been known to persuade couriers to swallow drugs in capsules in order to evade airport security, with potentially lethal consequences.
Ana Dinis, a young mother from Portugal, refused to swallow the drugs but did conceal 56 capsules within her own body.
"You know - about the risks," says Ana who is 23 and has a six-year-old child. She was sentenced to four years and eight months in jail.
"At that moment I didn't think, at that moment I was thinking about the money. So the risks, it wasn't, like, important to me.
"I knew I could be arrested, even die, because with these things you expect everything. But at that moment I was so desperate about the money, and to do something for my life."
It is also common to hear stories of drug mules who believe they were deliberately betrayed by the traffickers to allow others carrying larger quantities to get on to flights unimpeded.
The search for drugs continues as traffickers seek new routes
The police insist they work mainly with intelligence and detection, but roughly the same version of events was repeated to me by different sources. One young woman from Russia, who asked not to be identified, believes the police knew she was travelling with drugs.
"They knew my description and they were watching me as soon as I entered to the airport. I saw them looking at me and laughing. I saw them all the time looking," she says.
"They were dressed in normal clothes; they were not dressed in police clothes. And then they said, they said also they got a call from somebody."
The woman claimed that she was initially told that she would be carrying valuable stones, and when she realised it would be drugs, she was threatened until she agreed to continue.
After speaking to me, Sasha Brooks and Kimberley Anderson return to the routine of prison work - an area, along with their cells, I was not allowed to see.
These are anxious days for the two English women as they await sentence, as under Brazilian law they could receive between five and 15 years.
If they are lucky, because it is a first offence here and because of their age, it could be less.
Whatever their sentence, it seems unlikely they will be the last to take such a risk.
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