The fire broke out late Friday in a men's dormitory at Campsfield House detention center near Kidlington in Oxfordshire, The Independent reported. Part of the building's roof came down.
About 150 of the more than 200 people being held at Campsfield had to be moved, officials said Saturday.
Two men were hospitalized for treatment of smoke inhalation.
"All the detainees have been accounted for and two male detainees are now in hospital," the Home Office said in a statement.
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