A prison for young people is managed well but may have growing problems with attacks by groups on individuals, inspectors found.
Wetherby Young Offenders Institution was “well-led and effective” Her Majesty’s Inspectorate of Prisons said.
But inspectors also raised concerns that there was emerging evidence that assaults by groups of inmates on individuals were on the rise.
Chief inspector of prisons Nick Hardwick said: “Our overall assessment was that Wetherby was a well led and effective institution.
“It was safe and respectful, and although the challenges and risks of such a volatile and vulnerable group of young people were ever-present, there was confidence and focus among managers and staff that ensured the needs of young people were being met.”
The report followed an unannounced inspection at the institution, which holds about 230 juveniles, last October.
It did not include the specialist Keppel Unit.
The inspection did include the Anson facility, now the only dedicated juvenile unit in England and Wales for young people with life or long-term determinate sentences.
The report said the vast majority of inmates felt safe and were generally respectful of staff and bullying incidents were relatively rare.
The premises were clean and the use of on-site social workers helped with child protection.
And teaching was declared good and there was real evidence of improving achievements among young people.
But inspectors also found problems with self-harm rates and said conditions in the separation and care unit were “bleak”.
And young people continued to be admitted late and this made it more difficult for staff to settle them safely.
Michael Spurr, boss of the National Offender Management Service, said: “I am pleased that the Chief Inspector has highlighted the good work that is taking place.
“The governor and her staff should be commended for creating a safe and respectful environment, with good education and resettlement services that are helping to rehabilitate a challenging population.
“They will now take the recommendations forward.”