A medical charity says it has documented for the first time the effects of immigration detention on children facing removal from the UK.
Medical Justice, which sends doctors into removal centres, looked at 141 cases over six years.
More than 70 children were reported to be suffering psychological harm. Six girls, including an eight-year-old, had suicidal thoughts.
The government says it will end child detention, although it's unclear how.
Medical Justice has volunteer doctors, lawyers and caseworkers who examine the cases of about 1,000 detainees every year.
In its report, it reviewed a sample of cases between 2004 and this year in which clinicians had documented medical evidence of children who had been harmed by detention.
In approximately half of the 74 cases where children were reported to be suffering some form of psychological harm, the charity had been able to gain or conduct further assessments. In all of those cases, concerns supported the initial reports.
Children were found to be suffering from bed wetting, refusing to eat and exhibiting signs of regressions in their normal development. Of the six girls who had suicidal tendencies, three had gone on to attempt to kill themselves, said the charity.
The charity said that 92 of the children had reported physical health problems which had been exacerbated or caused by their detention. Some children were found to be coughing up blood and one child was reported to have begun suffering fits after he was detained. Others suffered swelling and asthma attacks
Medical Justice said that independent clinicians had been able to examine 55 of the children and confirm the initial diagnoses. In six cases, doctors reported to the charity that children had not been adequately investigated or treated for sickle cell disease.
Almost 50 of the children were recorded as having witnessed violence during attempts to remove their families, typically clashes between their parents and security officers. Thirteen of the children were reported to have been injured.
Jon Burnett, author of the report, said the government should accelerate its plans to end the detention of children, making good on the pledge in coalition agreement.
"The dossier of evidence we are publishing brings to light the extent to which detaining children cases harm, suffering, and anguish," he said.
Earlier in the summer, Deputy Prime Minister Nick Clegg said the detention of 1,000 children during Labour's last year in government was a "moral outrage". He confirmed that the family unit at Yarl's Wood removal centre in Bedfordshire would close.
But the Home Office has already missed a deadline to review the current system and publish proposals for a "new family removals process".
Ministers say that during this "transitional period" families will not be detained "unless there has been significant effort to secure voluntary departure and an attempt to enforce return without the use of detention".
Campaigners against child detention are however suspiciuous that the government may not completely end the practice. In the Commons earlier this week, immigration minister Damian Green spoke of "minimising" child detention.
The charity Barnardos, which is working with officials on alternatives, has already acknowledged that the UK Border Agency may need the power to hold children in detention facilities "for very short periods" prior to removal flights.
The former Labour government faced a long campaign from doctors, charities and child welfare experts against its policy of allowing immigration officers to hold families with children prior to deportation from the country.
Two of the harshest critics of the family units were the recently retired prisons watchdog, Dame Anne Owers, and the former Children's Commissioner for England, Professor Sir Al Aynsley-Green. The commissioner told the Guardian he had been "appalled" by the "litany of human misery", describing children as deeply traumatised children by being locked up.