Mobile phones shrinking from the bricks of the 1980s is a development welcomed almost universally, but it has had one unfortunate effect: prison visitors can now smuggle slimline models more easily to inmates.
A report by the UK's chief inspector of prisons says warders at Belmarsh jail in south-east London discovered four mobiles in prisoners' cells in May alone.
A spokeswoman for the Prison Service said the devices were brought in "intra-anally or intra-vaginally". She argued that, short of contravening European human rights legislation or obtaining warrants every time, it was virtually impossible to prevent this type of entry for contraband such as mobiles and drugs.
Although prisoners have access to regular fixed-line phones inside, and only Category A inmates have all their calls monitored, other prisoners are thought to have sinister reasons for wanting their own devices.
"We believe they're using them to harass witnesses," the spokeswoman explained.
One way around the problem would be to put all prison visitors behind glass partitions, as happens in the US. But the approach in the UK has been to allow physical contact in open rooms.
Asked which models were the most popular for concealment about the body - a potential new marketing angle for manufacturers - the spokeswoman said that no such details were available.
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