The true cost of using detention centres to lock up failed asylum-seekers has been exposed by statistics showing the extent of self-harm among those held.
Figures show that in the last four months of 2007, 42 people needed medical attention for self-harm in Britain's 10 centres.
This represents 2 per cent of the 2,095 people held at that time. As well as these cases, one in five people held were considered to be at risk of self-harm and being formally observed. Colnbrook detention centre, near Heathrow, was worst, with 18 cases of self-harm treated in four months, and 126 people under formal watch.
Meanwhile, at Yarl's Wood in Bedfordshire, where this week mothers have been on hunger strike in protest over the detention of their children, 52 inmates were under formal watch, and eight people required medical attention because of self-harm.
The statistics, obtained under the Freedom of Information Act, support the views of many immigration experts and MPs that prolonged detention of migrants is unethical.
A spokeswoman for the Refugee Council said: "These figures confirm our huge concerns about detaining vulnerable people for indefinite periods. Many of these people will have undergone extreme trauma and in some cases torture and detention in their home countries.
"We urge the Government to consider alternatives to detaining people, given the severe effect it has on their mental health."
Emma Ginn, of the National Coalition of Anti-Deportation Campaigns, said she hoped the statistics would act as a wake-up call to the UK Border Agency.
"Some self-harm attempts are just a cry for help, but some of these were serious suicide attempts. Why would any so-called bogus asylum-seekers make an attempt on their life? It's an indication of the living hell that they're going through."
Ms Ginn believes that the only option is to close the centres. "An alternative must be found," she said, "because they're driving people to make attempts on their own lives."
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