A young offenders' institution in Kent has become less safe and more violent, according to inspectors.

During a visit to Cookham Wood in Rochester they also found most of the 161 boys being held there were spending more than 19 hours a day in their cells.

The regime at Cookham Wood youth prison was poor and the risk of violence has increased, the report revealed.

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The HM Inspectorate of Prisons (HMIP) report followed an unannounced visit in August last year, and outlines a number of failings at the Rochester site.

The inspectors found education and therapy at Cookham Wood was "undermined by a custody regime which kept them locked in cells while skilled and enthusiastic professionals waited for them in empty rooms."

Difficulties in getting the 15-18-year-olds out of cells to attend the wide range of group-based services available led to a “significant waste” of resources, HMIP said.

The report noted that Cookham Wood had “many redeeming features,” including some enthusiastic staff, and that "the vast majority of teaching, learning and assessment was good and boys achieved very well," adding: "Individual work was complemented by a range of focused group sessions, including art therapy and managing emotions and resilience groups."

But it added: "Difficulties remained in getting boys to group sessions, largely because of the lack of escort officers. Between April and June 2017, about 40% of planned groups had been cancelled, which was a considerable waste of this valuable resource."

"The poor regime and delays in movements affected access to all services and represented a significant waste of resources as professionals waited in empty rooms for boys to arrive."

The youth prison was also found to be less safe and more violent than at the previous inspection in 2016, with little evidence of an effective strategy to reduce violence.

Peter Clarke, HM Chief Inspector of Prisons said: “While we did not underestimate the risks presented by some of the boys at the establishment and the need to manage their movements carefully, some of the unlock procedures were unnecessarily cumbersome and created further delays to an already curtailed regime.

“The main prison regime was also poor and unpredictable. The lack of time out of cell restricted access to education, interventions and meaningful interaction with staff and other boys.

"What was perhaps most unforgivable was that there were many skilled staff and partners who were keen to work with boys to help them progress but their efforts were frustrated by the failure to unlock boys on time, if at all.

"We were told by numerous professionals that this was not uncommon.”

HMIP noted that the YOI estimated the average time out of cell over the previous six months before the inspection to be about 4.5 hours a day.

However, a significant number of boys received far less.

Strengths at Cookham Wood included work with boys in their early days in custody, when they were well supported in reception and on the induction unit.

Boys with potentially life-threatening medical conditions were encouraged to wear a medical alert wristband to help custody staff to ensure their safety, which was good practice.

Mr Clarke noted that a new governor had been appointed just weeks before the inspection and that inspectors were encouraged by his optimism and plans to address problems.

Michael Spurr, Chief Executive of Her Majesty’s Prisons and Probation Service, said: “Regrettably, staffing shortages did affect the regime we were able to provide for boys at Cookham Wood, which is why we prioritised the recruitment of staff last year.

"As the Chief Inspector points out, the quality of teaching and learning provision is good, and we were able to provide greater access to education and training prior to the inspection.

"More Officers are now in post, with additional recruits in training, and with these new staff in place, the Governor will be able to provide a more consistent regime, reduce violence and provide better support for the young people in his care.”

"What was perhaps most unforgivable was that there were many skilled staff and partners who were keen to work with boys to help them progress but their efforts were frustrated by the failure to unlock boys on time, if at all" - the inspectors' report

The Howard League for Penal Reform claimed no child was safe in the youth jail.

Charity chief executive Frances Crook said: “No child is safe in Cookham Wood prison. Violence is rife. Staff are resorting to draconian punishments. It is shocking that boys as young as 15 are being held in such conditions.

“I visited the prison myself less than two weeks ago, and I was very disappointed to find boys were being locked up all day.

"Unsurprisingly, the inspectors found the same – teenagers with nothing to do, staring at bare walls for days on end.

“When I visited, the quality of the food was awful. Children were being given a very impoverished diet, so they were supplementing it by buying sweets and biscuits.

“This is a prison regime that lacks affection and kindness and imagination and skill. It is damaging children.”

The Howard League legal team runs a free and confidential legal advice line for children and young people in custody.

The charity has received more than 100 enquiries in the last year either from or on behalf of children in Cookham Wood.

They include the case of a 15-year-old boy with significant mental health problems, who was claimed he was locked in his cell all day on Christmas Day and was allowed only one exercise session between Christmas Eve and New Year’s Day.