By Nick Thorpe BBC News, Romania

Much has been reported about the trafficking of humans for sexual or labour exploitation. But little has been written from the point of view of the traffickers. Nick Thorpe has been touring Romanian prisons, talking to those already convicted. And, where possible, also to their victims.

All those involved in trafficking have their own stories

This story starts one January night in the face-pinching cold. We abandon the car in the snow and crunch the rest of the way on foot, to a shelter for trafficked women near Pitesti, north of Bucharest. To meet the director, Jana.

It's evening, she's tired, and wearies quickly of my questions. "It's become something of a fashion," she says ironically, "for journalists to buy girls. Then to film themselves, like knights in shining armour, handing them over to me.

"And frankly," she adds, "I'm bored of it. And of reporters like you, asking to talk to my girls. Haven't they been through enough? When are you going to start harassing the traffickers?"

So I took her at her word, and went in search of them.

Winter has passed. The cherry tree in the front yard of the maximum security prison in Bacau, eastern Romania, has lost its blossom, but not yet grown its fruit. It's warm outside, but cold inside the prisoners' club.

On a blackboard at the end of the room, someone has written, "tolerance" (in Romanian, "tolerantia"), followed by the words: "To tolerate means to accept somebody. To accept means to care."

There are paintings by the prisoners on the walls, mostly of houses, or flowers, or trees. There is one of a bearded Christ, with tears of blood on his face, from a crown of thorns. Another shows a woman, in a blue headscarf, with blue tears.

International 'kingpin'

Ioan was convicted of trafficking nine girls to the UK. We sit on hard wooden benches. Not true, he explains. He had a timber business, exporting to Norway. Sometimes his workers accompanied him. He got a reputation in his town as someone who was good at getting visas.

One girl came with him as far as Sweden, then flew to Britain. Her friends said they would find her honest work. Instead they sold her to an Albanian pimp. Who sold her to another.

I feel like a ping-pong ball, bashed back and forth by diametrically opposed versions of the same events

At some point, she rang her boyfriend in Romania, and told him what had happened. One Albanian got 24 years in jail in the UK. Ioan got 10 in Romania. The Romanian police say he was the local kingpin of an international network, sending girls to Italy and Macedonia, as well as Britain.

He says he was a legitimate businessman - occasionally doing a friend a favour, and never for money. The police are equally convincing. I wish I could tell you who is telling the truth.

In Buzau, two hours drive south, we meet a woman trafficker. Ana wears a bright orange sweatshirt, and flirts cheerfully during the interview. When I pause the tape-recorder, to rack my brains for the next question, she offers one of her own.

"You wanted to ask for my phone number?" she jokes.

She is a strange case - a victim, turned trafficker. The police version agrees, up to a point.

She was taken to Bologna in Italy, by Romanian traffickers. There she was treated cruelly, as were all the other east European girls under their control.

Taking a risk

At some point she met "the Albanian" and fell in love with him. He promised her a new life together, if she would bring him girls from Romania.

Trafficked women are often forced into prostitution

She says she trafficked four girls. The police say it was at least 32. She says they knew what they were coming to do. They say they were tricked.

I met one, Alina, in a village nearby. When she was 17, she told me, she was befriended by a young man in the village shop where she worked, and offered a job as a waitress in Italy, washing dishes.

She and her girlfriend Alexa took a risk. There was no future for them anyway, they thought, in their sleepy, backward backwater of rural Romania.

They were put on a bus to Bologna, where they were met by Ana and told they owed the organisers of their trip 2,000 euros (�1,370; $2,545) each - for passports, clothes and travel.

The only way to work it off, Ana told them, was to sell themselves, 12 hours a day, for sex.

Three months of hell followed. For Alina, it ended with three days of beatings, during which her hair and her thighs were cut - for allegedly hiding money from the pimps. Bleeding and penniless, she was dumped on a bus back to Romania.

Her friend Alexa did not fare much better. After one failed suicide attempt, from which she still bears the scars, she managed to escape.

In the meantime, the police infiltrated the network. Both girls gave evidence against Ana, and others. Both fear the day they will be released.

Meanwhile Ana, in her cell, longs for that same day. Her son is four-and-a-half years old now. She wants to start a new life, she says. She only breaks down, when she speaks of him.

Between the organised crime, police, and those convicted of trafficking, I feel like a ping-pong ball, bashed back and forth by diametrically opposed versions of the same events. In the presence of the victims, I run out of words.

Sitting in her parent's garden, beside the vines, the spring onions, the lilacs and the bright clothes-line, as the last of the evening sun catches her face, Alexa, the second of Ana's victims, begins to cry.

"Even my boyfriend, the father of my baby girl, beats me sometimes," she says. "He calls me a whore."