The admission comes as an investigation into the escape by murderer Lee Nevins from Sunderland Royal Hospital nears completion.

A major manhunt was launched to capture the 24-year-old last month after he left the custody of two prison guards who had escorted him to the city from Durham's Frankland jail, where he is serving a 17-year term.

The incident led to questions about security when convicts are taken out of prison for NHS treatment.

In a reply to a Freedom of Information request from the Echo, Sunderland Royal bosses said: "It is not the responsibility of the hospital to provide any arrangements to prevent
escapes – that is the responsibility of the prison service."

City Hospitals Sunderland NHS Trust said outpatient and surgery dates are often arranged two to five weeks in advance, at times convenient to the prison involved.

The trust added: "Nursing staff in the actual area of treatment would usually only know a prisoner was due in the day before the appointment when notes are prepared for the next day.

"Security staff are not routinely informed as the security of the prisoner is the responsibility of prison staff."

The trust also gave details about policies to protect staff and patients.

"Individuals are seen as quickly as possible to minimise any time waiting.

"Nursing staff ensure that the prisoner and prison officers are taken immediately to a treatment room so they are not waiting with other patients.

"Prisoners are seen in areas where the silent staff attack system is in place which allows hospital security staff to respond immediately should the alarm be raised.

"Trust security staff also have radio back-up."

Hospital chiefs said a "full root cause analysis" was undertaken following the Nevins incident, and procedures would be amended if necessary.

Police caught up with Nevins in Tillicoultry, central Scotland, six days after he left Sunderland Royal.

The Ministry of Justice said a draft report is almost ready following an investigation into the incident, but would not be made public.

Three men, aged 16, 19 and 23, were arrested on suspicion of assisting an offender, following investigations into Nevins's escape, and bailed pending further inquiries.