As the BBC's Social Affairs correspondent Alison Holt reports, a significant number of children are working as prostitutes but the adults who exploit them face relatively minor charges.

Children as young as 12 are working as prostitutes

Samantha was just 14 when she started working as a prostitute.

Her story is typical of many of the children who according to the charity Barnardo's are forced to work in this world.

Samantha's story

They fall in love with an older boyfriend, who gradually forces them to earn money by selling themselves.

Samantha's boyfriend started off showering her with love but then beat her up. Frightened and alone, she was kept a virtual prisoner in the sauna and flats where she worked.

Sara Swann : 'The law is completely out of date'

Sara Swann runs a Barnardo's project working with young prostitutes in Bradford. She says they have seen girls as young as 12 and 13 working as prostitutes.

It is impossible to know the true extent of the problem, but the charity has carried out what it believes is the first limited survey.

In one year it says 48 agencies such as charities, police and social services had contact with at least 267 girls under 16 and 338 aged 16-18.

The problem was not confined to the red light areas of cities.

Most disturbingly there seems to be plenty of men willing to buy sex from a child and plenty of others willing to be their pimps.

Sara Swann :'The man purchasing sex should be seen as a sex offender'

According to Sara Swann the law is completely out of date, as at the moment the pimps are only prosecuted for living off immoral earnings and the clients are done as kerbcrawlers.

Barnardo's is now launching a campaign to change the law.

Tim Brain of ACPO :'The law certainly needs looking at'

The government has already announced it will be reviewing the law covering this area, and a number of police forces are running pilot schemes where young prostitutes are treated as victims and not as law breakers.

That way the girls can be helped to get away from that type of life.

Tim Brain :'The law needs changing'

Deputy Chief Constable Tim Brain speaks on the subject for the Association of Chief Police Officers. He believes altering the law won't be easy, but says it certainly needs looking at.

At 17 Samantha has escaped from her violent boyfriend, and says she no longer works as a prostitute.