Levels of violence at a youth jail remain too high inspectors have said, as a report reveals gangs of boys have been attacking individuals.

There had been 127 reports of violent incidents in the six months leading up to the HM Inspectorate of Prisons’ visit to HMYOI Cookham Wood.

Of these, 33 were recorded as assaults on young people, 30 as assaults on staff and 58 as fights. Some incidents were very serious and involved gangs of boys attacking a single young person.

The young offender institution in Rochester holds boys aged 15 to 18. At the time of the inspection in September, there were 156 inmates with space for a total of 196. The teenagers come from across the south east and have been remanded for a variety of crimes.

In a report published on Tuesday, inspectors said too many incidents were serious and involved multiple assailants and that they were also concerned by the severity of attacks on staff.

Assaults on staff had increased by nearly a third since the last inspection and some were very serious.

There had been a reduction in the number of violent incidents in the months leading up to the inspection, but inspectors said the number remained too high.

They also said they were not assured that the figures accurately reflected the level of violence, and the actual number of incidents could have been higher.

Use of force had also increased, with 480 cases in those six months. It was mainly used to restrain and protect boys in fights and assaults.

Most incidents involving use of force were spontaneous in response to fights or assaults and began very quickly, with little warning, and involved groups of boys attacking each other or single victims. Inspectors said they saw examples of staff behaving bravely in these situations.

In these cases, each use of force was recorded as a separate case even though it was a single violent incident. For example, inspectors saw an assault on one boy involving six assailants that was, correctly, recorded as six separate use of force incidents.

The report said despite some significant and innovative work to tackle the levels of violence, this work was not yet embedded.

Inspectors visit Cookham Wood annually and at the last inspection in May 2015, were encouraged by the progress. The unannounced inspection in September found the progress had been maintained, but some safety concerns remained.

Chief Inspector of Prisons, Peter Clarke said: “This is a very positive report concerning an institution that continues to improve.

"Difficulties, risks and weaknesses were being attended to in effective and often creative and innovative ways right across the prison, and it was clear to us that even more improvement was very achievable quite quickly.

“The prison was led with confidence; the management team seemed cohesive and attentive and an evident strength was the quite impressive culture that was developing among the staff as they grew in both experience and confidence.”

Concerns were raised about the late times at which boys arrived at Cookham Wood which undermined the settling in process; work to promote family ties remained weak despite visits provision improving; and some sentence plans paid insufficient attention to the risks young people posed – of harming others and of reoffending.

Inspectors were pleased to find that safeguarding and child protection arrangements were well developed; the care offered to boys at risk of self-harm was good; and staff were knowledgeable, caring and working patiently with some boys whose behaviour was very difficult.

Michael Spurr, Chief Executive of the National Offender Management Service, said: “I am pleased that the Chief Inspector has acknowledged that Cookham Wood continues to improve, which is to the credit of the governor and his team.

“There remains more to do, particularly on safety, but work is under way to address this, including the introduction of a new behaviour management strategy and a new unit dedicated to supporting the most challenging offenders.

“The professionalism and commitment of the staff is a real strength and the strong foundations that are now in place will allow the prison to address the recommendations in this report and drive further improvements over the coming months.”

Most of the residential units were new, with much of the prison having been rebuilt in recent years, although some areas were grubby.

Time spent out of cells had increased but more than a quarter of boys were still locked up during the working day.

All the boys had daily access to vocational training and education, achieved qualifications and the quality of teaching was good but more needed to be done to prevent routines being disrupted, which affected attendance and punctuality.

Work to support boys resettling back into the community remained reasonably good, with excellent support from the casework team; and several new offending behaviour interventions had been introduced.

Prison reformers have called the report disappointing however.

Frances Crook, Chief Executive of the Howard League for Penal Reform, said: “A child is assaulted every six days in Cookham Wood, and it is surprising that a prison can be said to be performing well overall when the level of violence is so high.

“Particularly concerning is the report’s suggestion that a new progression unit was an appropriate response to the main challenges the prison faces in managing behaviour. Children have told us that the very first step in that scheme is at least a week in solitary confinement.

“It is also concerning that inspectors deemed governance of adjudications to be reasonably good. Research by the Howard League has shown that the number of additional days’ imprisonment imposed on boys in Cookham Wood rose by a staggering 279% in the space of 12 months – from 207 in 2014 to 784 in 2015.

“Prisons, especially those holding children, need to be encouraged to focus on a full and active regime, with suitably qualified staff, rather than managing the inevitable consequences of keeping boys cooped up for hours on end.”