Concerns have been raised about a growing drugs problem at a Kent prison.

Staff at HMP Maidstone, which holds nearly 600 foreign prisoners, have been warned not to be complacent about worrying signs that the issue is worsening.

It comes after an unannounced inspection carried out in October found 11% of prisoners who competed a questionnaire said it was 'very easy' to get hold of illicit drugs while behind bars.

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Another 7% of prisoners asked admitted to developing a problem with illicit drugs since arriving at the prison, with 8% saying they had developed a problem with medicated drugs not prescribed to them since being there.

The findings have been released in a new 130-page report published today.

Prison inspectors say the site was calm and well-ordered however the number of violent incidents and the use of force by staff had increased since their previous visit in August 2015.

Nevertheless, levels were lower than in most similar category C prisons.

Peter Clarke, HM Chief Inspector of Prisons, said: “In terms of behaviour management, it was good to see what we have recorded as good practice in the use of incentives and earned privileges.”

However, he added: “I would sound a note of caution about the… impact of illicit drugs.

"The prison, unlike so many others, had not been destabilised by an influx of drugs, but there were some worrying signs.”

The positive test rate in random tests of prisoners had risen and now stands at 14.5%.

“This was too high to be taken lightly," said Mr Clarke.

"Shortly after this inspection some 15 parcels containing contraband, including drugs, were thrown over the wall into the prison in the space of a single night.

"Despite the clear indications that drugs were a growing problem, the response to intelligence was poor, with backlogs and suspicion searches not being carried out in a timely fashion or at all.

"There was clearly a need to refocus on the strategy for reducing the supply of illicit drugs, and there is certainly no room at all for complacency.”

It was noted the security department received an average of 425 intelligence reports each month but still "intelligence was poor" and "supply reduction strategy was underdeveloped".

The report said: "Reports were generally of good quality but they were not always processed or communicated swiftly to appropriate areas.

"Intelligence-led searching and suspicion drug testing were not always carried out promptly. However, actions that were completed resulted in positive outcomes.

"During the previous six months, searches had resulted in the recovery of 48 mobile phones, eight SIM cards and 102 drug packages."

It was also found that random drug testing took place on set days and therefore "remained predictable".

The report said: "During the previous six months, 15 of the 36 positive tests had gone unpunished because test results were processed too late. This was unacceptable.

"The mandatory drug testing suite was a poor environment and the lack of a designated key meant that the area could be accessed by anybody. This was inappropriate."

Inspectors found medicine administration was safe and well supervised by prison staff, however, no officer was present during the administration of controlled drugs, including methadone.

Inspectors found generally good relationships between staff and prisoners “and a higher than usual proportion of prisoners told us they were treated with respect by staff.”

However, much of the residential accommodation was old, shabby and in need of refurbishment and the sports hall had been condemned and closed.

There were serious problems with laundry arrangements, causing prisoners to have to wash and dry clothes in their cells.

One of the most serious concerns was the decline in terms of the purposeful activity available to prisoners.

Mr Clarke said: “For those in employment the amount of time out of cell was perfectly adequate, but there were only sufficient activity places for around three-quarters of the population.

“Far too much of the work that was available was mundane and menial, and I was surprised to see large numbers of prisoners in workshops playing games rather than being engaged in work.”

In contrast, rehabilitation and release planning had improved since the last inspection, though Mr Clarke added: “Those prisoners who were destined to be held in detention under immigration powers at the conclusion of their sentence should have been told that this was going to happen sooner rather than later, and certainly not left until very close to the time when they anticipated that they would be released.”

Notable features from the inspection:

• About 20% of prisoners had never received a social visit.
• 51% of the population were black and minority ethnic men.
• The prison had a young population, with 40% of men aged under 30.
• A total of 93% of prisoners said that they had a faith.

Overall, Mr Clarke said: “The prison was completely aware of the distinct needs of their population, although more needed to be done to understand the more negative perceptions of their treatment and conditions held by prisoners with protected characteristics.

"The establishment also needed support in terms of investment to get the fabric of the buildings back to an acceptable standard and facilities such as the sports hall restored.”