Question to the Home Office:

To ask the Secretary of State for the Home Department, how many (a) irregular migrants and (b) asylum seekers are held in prisons under immigration powers.

As of 3 November 2014, there were 385 detainees held in prison solely under immigration powers. The information provided above is based on management information only and has not been subject to the detailed checks that apply for National Statistics publications. These figures are provisional and are subject to change.

It is not possible to distinguish irregular migrants from asylum seekers without the examination of individual records at disproportionate cost.