A "significant" use of weapons by inmates of a prison for teenage boys has been discovered by inspectors who have warned violence at the jail is "high and rising".
Some 35 weapons were found in a recent lockdown search at Cookham Wood, a youth offenders institution in Kent, Her Majesty's Inspectorate of Prisons (HMIP) said.
Inspectors said during the six months before the inspection, 169 acts of violence were recorded, compared to 130 at the previous inspection with 103 recorded as assaults and 66 as fights between boys.
Cookham Wood, which holds sentenced and remanded boys aged 15 to 18-years-old, was operating on a restricted regime at the time of inspection due to staff shortages.
Frances Crook, chief executive of the Howard League for Penal Reform, said: "Reading this report, it is hard to avoid the conclusion that it is now government policy to put children in danger and to create an environment where violence is festering.
"Cuts have pushed the prison system to breaking point.
"Staff shortages at Cookham Wood have led to a restricted regime, where some children are locked in their cells for 22 hours a day, staff are reliant on violence to control children and assaults and serious injuries have become the norm.
"The serious concerns identified by inspectors are common to most other prisons.
However, this report shows that ill-thought government policies mean that the prison system cannot keep children safe. This is a new low."
Serious injuries following fights and assaults were not uncommon, the inspectors said.
HMIP watched more than a dozen videos of incidents which revealed the use of weapons, attacks on individuals by multiple assailants and "reckless" behaviour by boys, including kicking and head stamping.
Chief inspector of prisons Nick Hardwick said: " We inspected Cookham Wood at a tough and challenging time.
"A new governor had recently been appointed and there had been significant loss of staff, not all of whom had been replaced."
He added: "Outcomes had suffered but the institution was sighted and there was evidence that issues were beginning to be gripped, so there remains every reason for optimism about the outlook at Cookham Wood.
"However, risks remain and the need to recruit suitable new staff is fundamental to the future success of the prison."
Michael Spurr, chief executive officer of the National Offender Management Service (NOMS), said: "The Governor is actively tackling violence within the prison.
"Staff are being provided with additional training in behaviour management and all serious incidents are being referred to the police. Use of force has reduced and we are actively recruiting new staff to fill vacancies."