Watchdog call conditions and Luton Airport Detention Facility 'UNACCEPTABLE'
A total of 17,445 people were detained in such holding centres between June and November 2023
A watchdog has criticised "unacceptable" conditions at the busiest airport immigration detention centre in England and Wales.
Chief inspector of prisons Charlie Taylor said the facility in Luton was "unable to cope" with demand and raised concerns that children were being put in crowded holding rooms with adults they were not related to.
Migrants were being held for "far too long" in facilities ill-equipped for long stays, the watchdog also warned in findings published on Monday.
Most UK airports have short-term holding facilities to detain people who have just arrived in the UK on flights or have been brought from other detention centres to be removed from the country. The conditions are inspected by the prisons watchdog.
Inspectors found Mitie Care and Custody-run facilities for holding detainees for short periods of time were "generally suitable" but highlighted "wide variations" among different airports.
A total of 17,445 people were detained in such holding centres between June and November 2023, with several people being held more than once.
Of these, 2,898 people were detained in the facilities at Luton airport during that time - a higher number than any of the centres at Heathrow terminals or Gatwick, partly because of the "high number of flights going to and from Eastern Europe."
The report, which set out findings from an inspection carried out in January, said: "Luton was simply unable to cope with the demands placed on it and we were particularly concerned to find that children were placed in crowded holding rooms with unrelated adults.
"By contrast, the new facilities at Manchester provided a well-designed and reasonably comfortable environment."
"The most urgent challenge for the Home Office is to find a solution for the unacceptable conditions at Luton", the report added.
Despite being only intended to hold people for a few hours at a time, the watchdog found more than a quarter of people (27%) detained in the five-month period in airport facilities across England and Wales were held for more than 12 hours and nearly 600 people - including six children - were detained there for more than 24 hours (581 or 3.6%).
The average length of detention during the period was nine hours and 12 minutes, with the longest recorded period of detention being 56 hours and 51 minutes.
Detainees were not allowed access to prescribed medication and phone calls were limited at many sites, according to the report.
The findings also raised concerns that not all Border Force staff who had contact with children had the appropriate safeguarding checks.
A Home Office spokeswoman said: "We work at pace to ensure detention in holding facilities is for the shortest time possible and prioritise the processing of children and vulnerable people.
"Individuals in detention are held in safe and decent conditions, and we have improved facilities and medical support in recent years."
The department said it had "already taken action" to address some of the recommendations and pledged to "continue working closely with the inspectorate to deliver further improvements."
A Mitie spokesperson said: "It is positive to see the report acknowledge the "sensitive and clear" interactions between our colleagues and detainees as well as recognition of the "good working relationships" between ourselves and Border Force.
"The safety and wellbeing of those in our care remains our priority and our focus on safeguarding has also been noted in the report.
"We are working closely with colleagues and the Home Office to ensure the good policies and practices we have put in place are offered consistently."