Failed asylum seekers at Campsfield House Immigration Removal Centre used the Internet to access “inappropriate content” on the web, it has emerged.

A report by Her Majesty’s Inspectorate of Prisons (HMIP) revealed the centre’s 200 plus detainees were accessing the worldwide web for up to an hour a day, but “despite controls, arrangements to block access to inappropriate content were not always effective”.

Last night, a spokesman for HMIP could not detail the nature of the inappropriate content, and chief inspector of prisons Anne Owers was unavailable for interview.

However, Ms Owers released a statement which read: “Email and Internet access is an important, and cheap, way for detainees to keep in contact with the outside world and relatives overseas. It is, however, important to ensure that access is controlled.

“The point of the comment in the report is that there was a system of visual and spot checks at Campsfield, but the most effective way of ensuring that access is consistently controlled, which we have observed in other centres, is either to have a filtering system, or for staff to have a monitoring screen on which they can see exactly what all detainees are accessing.”

Detainees first began surfing the web in December last year and there were plans to create an Internet cafe, HMIP revealed.

Inspectors compiled the report after an unannounced four-day inspection of Campsfield House, near Kidlington, in May this year.

The centre had “returned to normal” following a series of “major disturbances” in 2007, which included two riots and a breakout by 26 detainees, the report said.

However, the inspection took place a month before another outbreak of violence and the escape of seven more detainees, and those incidents were not mentioned.

Inspectors also found detainees were given pay-as-you go mobile phones on arrival at the centre, which the Home Office said were returned whenever a detainee was removed.

The report found there was little evidence of bullying.

The report also showed that the average length of detention had more than tripled, from 14 days in December 2006 to 46 days.

Bill McKeith, of the Campaign to Close Campsfield, said: “The overall flavour of the report is quite critical. The Government claim it is a removal centre. A removal centre is a place where people are placed briefly before they are removed — and 46 days is not a brief stay.”

A spokesman for the UK Border Agency would not be drawn on Mr McKeith’s claims, and did not issue a reaction to the report.

Nobody was available for comment at GEO Group UK Ltd, which runs the centre.

The inspectors also recommended an investigation as to why there had been a 37 per cent turnover of custody officers in 12 months.

The report also gave a detailed breakdown of the nationalities and ages of the 202 detainees.

Twenty-two detainees were from Nigeria, 20 from Afghanistan, 16 from China, 13 from Jamaica and 12 from Pakistan.