Inmates in the biggest jail in Britain are ordering drugs, continuing to run criminal activities and plotting escapes using mobile phones that are smuggled into the building, according to a watchdog report.

The “apparently limitless” supply of mobile phones in Wandsworth prison is increasing the supply of drugs on the wings as well as “fuelling a whole group of new users”, the report said. Almost 250 mobile phones were found inside Wandsworth, in southwest London, in the first five months of this year, the report from the prison’s Independent Monitoring Board disclosed.

“We still have very serious concerns about the apparently limitless supply of mobile phones in the prison that drive the easy availability of drugs and that are also used in bullying and intimidation,” the report, which covers 2006-07, said. “Mobile phones are used to facilitate the delivery of drugs to prisoners, continue criminal activities from within, pressurise vulnerable prisoners, contact families of prisoners and staff, plan escapes, bullying, intimidation and a host of other unsavoury activities.”

The report said that it was only a matter of time before a “very serious incident” took place because of mobile phone use. It said that more officers should be on duty during religious services to prevent worship being used as a cover for illicit activities, particularly drug dealing. It added that for three years it had warned the Home Office, which until earlier this year had responsibility for prisons, about mobile phone use by prisoners, but no effective action had been taken.

The board called for a jamming system around the prison but it is understood that this cannot be done because it would affect the use of mobile phones on roads outside.

The report said that a schism among Muslim prisoners about the imam at the prison, which developed in 2005-06, remained an issue but was being handled sensitively. It said that there was evidence that some prisoners were forced to adopt “more militant lifestyles”. The imam has been replaced.

The board also criticised the delays in deporting foreign prisoners who have served their sentences but are kept in the jail awaiting deportation. Two immigration officers are dealing with outstanding cases.

“A number of nationalities give us major concerns,” it said. “Somalis, for example, have no active diplomatic representation in this country. We now have a number of Somali prisoners who have been incarcerated well past their release date who want to go home and there seems to be no prospect to facilitate this.”

The board said that conditions at the prison had improved in the past 12 months, with prisoners spending much more time out of their cells, a fall in the use of control and restraint and greater levels of satisfaction with the treatment of prisoners by staff.

Every prison in England and Wales must, by law, have an independent monitoring board made up of local people. The board must satisfy itself of the humane and just treatment of inmates, inform the Secretary of State for Justice of any concerns it has and publish an annual report.

Behind bars

1,485 prisoners are in Wandsworth jail

100 have life or indeterminate sentences

30% are foreign citizens

Source: Independent Monitoring Board

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