Some of the most vulnerable children are being failed by the criminal justice system, ministers have been warned.
The extent of the crisis was revealed last night in the wake of the apparent suicide of the youngest prisoner to die in custody in Britain. Record numbers of young people are being locked up, with child jails and young offenders' institutions operating at maximum capacity.
The number of children held in secure accommodation has risen by 50 per cent in the past 10 months alone, according to figures from the Youth Justice Board. Staff are struggling to cope with soaring rates of self-harm and mental health problems among detainees.
Children as young as 12 are subjected to strip searches, solitary confinement and restraint procedures that have resulted in the death of a 15-year-old boy this year.
A day after 14-year-old Adam Rickwood became the first youngster to die in the new breed of child prisons which were introduced under Labour, and the youngest person to die in custody, campaigners called on the Government to hold a public inquiry into the youth justice system.
Frances Crook, the director of the Howard League for Penal Reform, said: "David Blunkett [the Home Secretary] has the blood of children like Adam Rickwood on his hands.
"There is a gross overuse of custody for children in this country and the system is full to capacity. We are failing these most vulnerable of children and we are therefore also failing future victims of crime.
"The criminal justice system for juveniles is highly punitive, vengeful and abusive - and unless something changes, Adam's tragic death will not be the last."
As of yesterday, there were 2,637 people under the age of 18 in detention in England and Wales, a rise of 50 per cent since November last year.
The number has doubled since 1993, with campaigners claiming that the Government's "obsession" with being seen to be tough on crime has led to the increasing use of detentions by the courts.
Juvenile offenders are held in three types of detention. The majority (2,123 boys and 70 girls) are held in young offenders' institutions, with a further 208 boys and 48 girls detained in local authority secure care homes. Additionally, 66 girls and 122 boys, ranging in age from 12 to 17, are locked up in three secure training centres.
The training centres were opened in 1999 as purpose-built "child jails" designed to hold young criminals, but with an emphasis on education, training and rehabilitation. Designed to operate at about 90 per cent capacity, they are now running at 95 to 100 per cent most of the time.
Ellie Roy, the chief executive of the Youth Justice Board, admitted that the high rate of detention meant that the system did not have the flexibility it needed. But she said that the training centres and the rest of system did their best to help children in their care.
Ms Roy said: "It is not perfect and we always want to improve things, but I think it would be wrong to caricature it as being draconian and brutal.
"We have hugely committed staff doing their best with very troubled and sometimes very troublesome children. "The children being looked after in these places have very, very difficult backgrounds - more difficult than the average person in the street could even imagine.
"Lots of them have mental health problems, they have have used drugs and have been abused physically, sexually and emotionally.
"It can be very difficult to control them. They come into the system in a state of crisis." She added: "These are children who are often not being cared for at all in the community, and have been failed in many ways, and it is establishments such as the [training centres] that are then trying to give them some kind of control and order in their lives.
"I think it is wrong to point the finger of blame at secure establishments, because the blame for these children's problems lies across society." The scale of problems suffered by the young detainees in the criminal justice system is alarming.
A recent study found that a total of 85 per cent of 16- to 20-year olds in young offenders' institutions showed signs of a personality disorder and 10 per cent had symptoms of psychotic illnesses such as schizophrenia. Two thirds of women under 20 in prisons and young offenders' institutions had a record of self harm.
Figures from the Youth Justice Board show that there were more than 200 incidents of self harm in the three training centres alone last year.
Juliette Lyon, the director of the Prison Reform Trust, said: "Young offenders' institutions hold some of the most damaged and distressed young people in our society. For the majority of young people, imprisonment will compound rather than resolve their difficulties.
"Prison is often the cheapest form of disposal for difficult and disturbed teenagers, but arguably the least effective in the long term." Lobby groups say that the training centres are too brutal for children who, like Adam, may never have been detained before.
Ms Cook said: "I visited a training centre and it was more obsessed with security and control than any maximum security adult jail I have ever visited.
"Children have absolutely no rights. If they walk across a courtyard, an announcement is made over the public address system. They cannot play football because no more than 10 of them are allowed together at one time.
"There is excessive use of strip-searching, restraint and solitary confinement."
She added: "You put someone vulnerable like [Adam] in one of these places, hundreds of miles from home and with this level of control, and a tragedy like his is inevitable."
Except for Ireland, England and Wales have the lowest age of criminal responsibility in Europe - from the age of 10, compared with 14 in most other EU countries, children are channelled through the penal system.
Other figures also give the lie to popular - and populist - opinions that the children who are detained are violent tearaways for whom a "short sharp shock" will work.
More than two thirds of children in custody are there for non-violent offences that do not involve violence, sex or robbery. And according to Ms Cook, a third of children reoffend within weeks of being released, rising to 85 per cent within two years.
The death of Adam shocked prison campaigners. Deborah Coles, the director of the charity Inquest, which campaigns against deaths in custody, said: "I remember that the first case I did for Inquest was a 15-year-old boy called Philip Knight who hanged himself in jail in 1990.
"His death sparked outrage. There were questions in the House of Commons, the Home Secretary ordered an inquiry and there was reform of the system.''
Ms Coles added: "What has shocked me so much about Adam Rickwood's case is that not a single minister has seen fit to comment and people just seem to accept that there will be children who die in custody. What does that say about our society?"
YOUNG PRISONERS WHO HAVE TAKEN THEIR OWN LIVES
Aged 16, from Coventry, hanged himself in his cell at Brinsford young offenders' institution near Wolverhampton in February 2001
In the days before his suicide, Redding complained of hearing voices, specifically that of his dead grandmother. After his parents removed him from school because of bullying, he became involved in car crime, and was given a four-month sentence for motoring offences in January 2001. He was frightened about returning to Brinsford, having undergone a two-month spell in custody in 2000.
Before his death, he was placed on a five-minute suicide watch - he had already tried to kill himself four times since his sentencing. But despite a history of self-harm, he was kept alone in a single cell. His mother, Helen Redding, said: "Anthony did not get the level of care he needed. He was a 16-year-old lad and his death was a cry for help."
Aged 16, hanged himself in Stoke Heath young offenders' institution in March 2002, nine days after beginning his sentence
After his parents' divorce, the Manchester teenager was subjected to repeated sexual abuse by a member of his father's family. Five months before his death, he took an overdose and jumped from a window. He was convicted of affray for starting a brawl with the ambulance staff who treated his injuries. Placed in "voluntary care", Scholes was soon under arrest again, this time for robbery. But before appearing in court he slashed his own face thirty times with a knife. In spite of his condition, the judge presiding over the teenager's case decided his circumstances were not sufficiently "exceptional" to warrant suspension of his two-year sentence. "The day he was sentenced, I knew he was going to die," Scholes's mother, Yvonne, said.
Aged 18, hanged herself at Brockhill women's prison in Worcestershire in January 2003. She was 12 days into her sentence
A heroin addict and single mother of a two-year-old son, Gidney had convictions stretching back to the age of 12. She had appeared in court on seven occasions prior to her final sentence, for robbery. The Rugby teenager had stolen £1 from three friends. A report in 2002 by Anne Owers, the chief inspector of prisons, criticised Brockhill for its drastic understaffing and its lack of adequate care for young inmates. Gidney's death sparked further criticism, notably from Juliet Lyon, director of the Prison Reform Trust, who accused the Home Office of providing insufficient support for women drug users in prisons.
Aged 18, originally from North Wales, took an overdose of anti-depressants at Styal women's prison in Cheshire in January 2003
When she was found guilty of manslaughter, the teenager had been distraught to discover that she was going to prison and not to a secure psychiatric hospital. Campbell was diagnosed with depression at the age of 15, but remained a talented artist and tennis player, intending to study fine art at university. She became addicted to heroin. She and another addict had stolen a 72-year-old man's wallet. Their victim was literally frightened to death by the incident, dying of a heart attack caused by shock. Pauline Campbell said of her daughter: "I think she felt rejected, abandoned. She was of above average intelligence and I don't think she could cope with what was happening to her."
Profiles by Tim Walker