Four men have been held for more than two years at Brook House immigration removal centre as the average length of detentions has grown, a report found.
Prison inspectors discovered the average period of stay at the facility near Gatwick Airport had risen from 28 to 48 days.
Twenty-three people were held for more than a year.
The Home Office said it did not want to detain people for longer than necessary but some had prolonged the process. Read the full story here .