Immigration detention centres are officially called Immigration Removal Centres, as their stated purpose is to hold people who the government intends to deport from the UK. Around half of people in immigration detention are asylum seekers, and many have family ties in the UK. Over 30,000 migrants are detained in the UK every year.
There are, at present, 11 detention centres in the UK. (This figure includes Short Term Holding Facilities.) Some are run by private security companies, others by the Prison Service. People in detention cannot leave and have very limited freedom of movement within the centres. Security levels are similar to prisons.
The UK is unique within Western Europe in that there is no maximum time limit on immigration detention. Whilst the maximum time limit for people to be detained in France is 45 days, in the UK detention is indefinite – people can be and are detained for months or even years. It costs, on average, more than £30,000 to detain someone for a year.