Most evenings two or three gutsy women board a minibus. They drive around the local red-light spots – streets frequented by prostitutes, the town centre, parks and seedy bed & breakfasts. They are looking for trouble or at least the potential for it: children vulnerable to sexual exploitation.
"If we see a 13-year-old girl with a can of beer on the streets or in a park at 10.30 at night, we stop," says Wendy Shepherd, the leader of the teams of specialist workers at the child sexual exploitation unit of children's charity Barnardo's in the North-east of England.
Sometimes they confront the pimps. They can be faced with harrowing situations such as the aftermath of sexual assaults. They work into the early hours.
There are such areas in most of Britain's towns and cities – and such children – even if most of the public prefer not to notice. The problem is far greater and more pernicious than most of us might imagine.
Wendy Shepherd's team routinely encounters children under 16 drunkenly tottering along the streets, or girls of 14 sitting on a wall in a known prostitutes' pick-up spot, or desperate young women of 16 upwards living in seedy bed & breakfast houses which can become a nest of drug-dealing and sex-for-hire. She asked me not to disclose the name of the town for fear of identifying and stigmatising the girls involved.
"Many of these are run by unscrupulous landlords only interested in collecting the rent direct from housing benefit," says Wendy, a bluff no-nonsense local woman with 15 years' experience in working with vulnerable children and adult prostitutes. "They can be terrible places with dirty, stained mattresses, filthy fridges, cookers that don't work – even with excrement and blood from previous tenants streaked on the walls."
Some of the tenants are insalubrious characters who offer free drugs to 16-year-old newcomers – and then demand they carry drugs locally as payment. "One girl told us that if she was forced to carry on living in such a B&B, she was convinced she would be raped by other tenants. Three days later she was," Wendy says. "Vulnerable young people shouldn't be put in the same places as adults with these kind of problems."
Among the seedier spots the Barnardo's team visits are the central bus station's toilets where graffiti regularly advertises that 14-year-old boys are wanted for sex.
"If you pick up a stone you'll find all sorts of things underneath," Wendy says. "And we're not afraid to pick up the stone."
Barnardo's is one of the three charities being supported by Independent readers in this year's Christmas Appeal. Its team has had significant success in co-operation with the local police and council. The town, which the local paper said a decade ago had the reputation as the region's prostitution capital, has since recorded dramatic falls in the number of kerb crawlers and prostitutes.
"Ten years ago there were 250 women on the streets here," Wendy says. "Now that's around 75. That success is down to a combination of a police crackdown on kerb crawlers and Barnardo's interventions which range from simply offering young girls a lift home to devising longer-term strategies to help young women find an exit from prostitution. "We offer the Barnardo's centre as a regular safe haven and we work with children and schools on prevention strategies to stop today's teenagers becoming tomorrow's prostitutes."
But a new problem is emerging. Increasingly young girls are being groomed by older men and invited to "parties" where they are coerced into sex with strangers. "It begins with a young girl, who may have had a major row with her mother and walked out of her home, being befriended by a man," Wendy says.
"They take them out for meals, buy them the latest mobile phone or snazzy trainers and generally charm them. Then, when they are convinced they have found a great boyfriend, they get invited to a party where he says: 'My mate fancies you, will you go to bed with him? You will if you love me.'" One of the girls rescued by Barnardo's explains the process from the inside: "My mum wasn't around anymore, my dad was drinking and my sister was skipping school," says Jess. "I was 15 and got involved with a group of friends outside school – they were older. At first I thought it was really cool to have older friends – they were drinking and there was a lot of drugs around.
"I was already drinking when I met them – it didn't bother me. But the drugs were new. I thought, if they were doing it, then it must be OK. And at first it was OK – I could get the money from my dad. But after a couple of weeks, I was getting hooked and there wasn't enough money.
"My new friends said that it was fine and introduced me to a man. They said he fancied me and that I should go out with him. I didn't realise what was happening – I was being set up. After I slept with him I realised that I'd been used but it was too late: I was hooked on drugs. The situation was frightening – but I didn't know how I could change things."
Various techniques are used to disempower the girls. "They get taken somewhere in a car," Wendy says. "They're not sure where they are, how they're going to get home. Or they go to the door at the party and find it locked. Or the 'boyfriend' says: 'You haven't told your mam where you are, so what are you going to say to her? Or they say: 'I've got photos of you; I'll send them to your Mam. You're on video; I'll put it on the internet if you don't co-operate. You're a slapper; who's going to believe you?"
They prey on the girls' confused feelings. Some say, "I like him, why is this happening to me?" Others feel guilty or ashamed which keeps them silent. Others get hooked into a relationship with a man who alternates charm, or constantly saying he's sorry, with coercion and threats.
Some of these trapped children attempt suicide. Others internalise the behaviour and make it their identity. There comes a point, Wendy says, where "in the end, they say, this is what I do." She says on average prostitutes start at 14.
Lizzie says: "It's really hard to talk about girls being trafficked in this country; no one wants to believe it." She was sucked into a kind of sexual slavery after she was taken into care when she was 12. "The girls in the home were all a bit older than me and were going out with older men. At first I just tagged along."
To a 12-year-old it all seemed very exciting. "They gave me drink and smokes – it was a laugh. Then one man started to take a special interest. He was much older, protective – I felt looked after, wanted, loved even. He gave me everything I wanted and when I was 13 he gave me the keys to a flat and said 'It's yours, use it when you need it.'"
With no family support and little self-esteem it seemed like a dream come true, but soon it was payback time. Her "boyfriend" asked her to dress up for a party. She was taken to London and told to have sex with some "friends" of his. Next came "parties" in Manchester and Leeds.
"He'd take me to hotels, some nights two or three," Lizzie says. "I wanted to escape, but he just controlled me – it was a mental thing, I was terrified."
Barnardo's tries to offer alternatives to children before they become enmeshed. One of those who has been successfully helped is Kaylee, who was 15 when a Barnardo's education worker visited her school. Her teachers had suggested Kaylee see her because all the risk signs were there: family problems, using alcohol and drugs and staying out at night.
Kaylee joined a Barnardo's project. It made her realise that she was being groomed for sexual exploitation. She says: "I didn't see myself as a victim, but I realised what was happening to me was wrong. Then one night I was raped. I didn't know what to do but I kept thinking about the lesson in school and although I was really frightened I found the address and went to Barnardo's."
Two years on, Barnardo's have helped Kaylee go to college, get a job and find her own place to live. "I knew the drugs and abuse wasn't my destiny," she says. "So I changed it – with the project's help."
Some names have been changed to protect the children in this article
The charities in this year's Independent Christmas Appeal
Children around the world cope daily with problems that are difficult for most of us to comprehend. For our Christmas Appeal this year we have chosen three charities which support vulnerable children everywhere.
* Children on the Edge was founded by Anita Roddick 20 years ago to help children institutionalised in Romanian orphanages. It specialises in traumatised children. It still works in eastern Europe, supporting children with disabilities and girls at risk of sex trafficking. But it now works with children in extreme situations in a dozen countries – children orphaned by AIDS in South Africa, post-tsunami trauma in Indonesia, long-term post-conflict disturbance in East Timor, and with Burmese refugee children in Bangladesh and Thailand. www.childrenontheedge.org
* ChildHope works to bring hope and justice, colour and fun into the lives of extremely vulnerable children experiencing different forms of violence in 11 countries in Africa, Asia and South America. www.childhope.org.uk
* Barnardo's works with more than 100,000 of the most disadvantaged children in 415 specialised projects in communities across the UK. It works with children in poverty, homeless runaways, children caring for an ill parent, pupils at risk of being excluded from school, children with disabilities, teenagers leaving care, children who have been sexually abused and those with inappropriate sexual behaviour. It runs parenting programmes. www.barnardos.org.uk