• RICHARD HOSKINS investigates how London became trafficking capital
• Children are used to trick the benefits system and for sex abuse rings
• A new United Nations report paints a dark picture of the British cap

BANGKOK. The little girl winks, then runs her tongue around her upper lip. ‘Do you want a good time, Mister?’ she says.

‘Come and have some fun with me. I’ve got a room nearby,’ she adds, describing the sex acts on offer in perfect English.

Too perfect.

‘Where are you from?’ I say.

‘London. Well, Nigeria.’

‘How old are you?’ I ask.

‘Do you like them young? I’m cute.’ She winks again.

Horror, revulsion and pity sweep me in equal measure. I make it clear why I’m here. I’m a researcher and she agrees to talk at the nearby cafe. Her name is Grace.

I knew I would encounter sex tourists: it is what I’ve been investigating for my next book. But I hadn’t expected to meet a child from Africa with a London accent on the streets of Thailand.

Grace explains she was brought from Nigeria to Britain where she was moved from house to house. Then, after two years, she was flown to Bangkok.

She works the streets under the watchful gaze of a pimp because even in the hypocrisy of Thailand she would be too young for the main sex bars.

Here, between Nana Plaza and Soi Cowboy, she has a ripe market of sex tourists, many of them British.

The more I ask Grace, the less she tells. She glances over her shoulder. There’s fear in her red-stained eyes. Eyes that have seen too much in so slight a body. For one thing I do discover: Grace is 12 years old.

I am an author and criminologist – you might know me from my work tracking down the killers of ‘Adam’, the African boy found floating in the Thames, the victim of a ritual killing – and I have spent 13 years investigating cases of exploitation just like Grace.

So where does the blame lie? My disturbing conclusion is that the roots nourishing her tragedy lie neither in Nigeria, nor in Thailand, but in Britain. And that, to our shame, we are doing nothing about it.

There is a clue, perhaps, in the alarming extent of the British trade in child pornography and in last month’s revelation that more than 600 abusers and potential abusers have recently been held by the police.

The true scandal, though, is bigger and more dangerous than the authorities acknowledge. Because London has become the hub, the epicentre for a global trafficking enterprise involving thousands of children for exploitation, sexual abuse and even, in some unspeakable cases, ritual voodoo killing, as a new United Nations report makes clear.