A worrying number of prisons are overcrowded, unsafe and provide inadequate purposeful activity for prisoners

Joe Levenson Prison Reform Trust

Of these, just over half were on the 67,259 inmates in English and Welsh jails.

Worst was Castington young offenders' institution in Morpeth, Northumberland, where 93% of inmates were assaulted last year - about 10 times the national average of 9.9%.

Other youth jails had high levels of assaults, with 62% at Brinsford in Wolverhampton, 61% at Huntercombe in Oxfordshire, and 54% at Ashfield in Bristol.

The adult prison with the highest assault rate was Wetherby, West Yorkshire, at 52%.

Record population

Last year the Prison Service met seven of the 13 targets which were then in force.

Report author Joe Levenson said: "The Prisons League Table shows that despite some progress the Prison Service is struggling to cope with a record prison population.

The Prison Service met its targets on overcrowding

"A worrying number of prisons are overcrowded, unsafe and provide inadequate purposeful activity for prisoners.

"Until these failing prisons are drastically improved, prisoners will continue to be held in damaging conditions with little to be done to prepare them for release."

The Prison Service also failed to ensure that 1,020 inmates completed the Sex Offender Treatment Programme, the report shows.

Just 786 achieved it, with the reason for failure being given as a lack of qualified staff.

However, the service did increase the number of prisoners completing reoffending programmes by 30%, beating their target by nearly a fifth.

�65m sick days

Staff sickness is still a huge problem, the tables suggest, with almost 597,000 working days being lost in the year.

Assaults in jails

67,259 inmates 6,388 recorded assaults 9.9% of inmates assaulted on average 93% of inmates assaulted at Castington YOI 52% assaulted at Wetherby Prison

This amounted to 13.6 days per worker and equated to a cost of more than �65m.

The tables, compiled from data in the Prison Service annual report, shows they met their targets on prison overcrowding.

However, the trust pointed out that officials did not consider two people being held in a single cell as overcrowding - which applies to 17.2% of the prison population.

The Prison Service improved on its target of no more than 16% of random drugs tests coming out positive, achieving a national average of 12%.

But some jails failed dramatically to meet the mandatory drugs test target, including Featherstone in Wolverhampton.

This reported the highest drug use for the second year running at 34% - followed by Blakenhurst in Worcestershire (30%), Leicester (26%) and Cardiff and Everthorpe in East Yorkshire (both 25%).

'No category A escapes'

A Prison Service spokesman said: "We will be working towards meeting our key performance indicators next year.

"We are pleased that we met our KPI ensuring that no Category A prisoner escaped from custody because protecting the public is one of our highest priorities."

The high number of assaults in young offenders' institutions was partly down to the fact they hold a "volatile cross section of the population", he added.

"However, they do not tolerate violence in any form. Anti-bullying strategies are in force in all prisons and any young offender who is found to have attacked or threatened another will be dealt with by the governor."

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