Hardline measures to curb anti-social behaviour are to blame for an unprecedented rise in the number of children, especially young girls, being sent to jail. A memo written by the Government's youth justice chief and leaked to The Independent on Sunday reveals that the number of teenagers in custody has soared over the past three months, with figures now at a three-year high - with a serious risk of suicide and self-harm.

In a personal warning to the Home Secretary, Charles Clarke, Ellie Roy, the chief executive of the Youth Justice Board, says that overcrowding has led to large numbers of juveniles ending up in prison-run institutions, which she warns are not appropriate for vulnerable children, and that some 18-year-olds may even have to be sent to adult jails if the situation continues.