PRISON staff have been warned about potential copycat crimes after an officer was taken hostage in a suspected terrorist attack.
A male officer had his cheekbone broken by three Islamic extremist prisoners during a four-hour stand-off at HMP Full Sutton, near Pocklington.
The Mail understands he was also slashed on his face and neck with a makeshift weapon by the inmates, who mistakenly believed he was an ex-serviceman.
A female officer suffered cuts to her arm when she tried to stop the inmates dragging the officer into a room.
During the siege, they were threatening to kill the officer while making "extremist demands".
Counter-terrorism police are now investigating after the attack at the high-security jail on Sunday. None of the prisoners were serving sentences for terrorism offences.
Staff at HMP Hull and HMP Everthorpe, near Brough, have been sent an email warning them there is a heightened risk of attacks following the siege and the murder of Drummer Lee Rigby in Woolwich, committed by Islamic extremists.
It also says the prisoners believed the officer was a former member of the Armed Forces. The Ministry of Justice confirmed neither officer was ex-military.
The internal email says: "All staff are advised there was a hostage incident.
"Three Muslim prisoners took an officer hostage in an office.
"Their demands indicated they supported radical Islamist extremism. They believed the officer taken hostage was an ex-serviceman and, throughout the incident, threats were made to kill him.
"All staff are reminded to remain vigilant to the increased risk of potential attacks on prison officers inspired by these and last Wednesday's events."
Both officers were treated in hospital and later discharged.
The Ministry of Justice said the officer was "forcibly" taken hostage at 4.25pm. He was rescued when specialist officers freed him at 8.40pm.
A statement from the Prison Officer Association (POA) union called for the "full weight of the law" to be brought against the perpetrators.
It said: "This was a disgraceful attack on prison officers that should be condemned.
"Prison officers do an extremely dangerous job on behalf of society. Only for the professionalism of police officers, this could have been so much worse."
Officers from the Full Sutton branch of the POA declined to comment.
A statement issued by the North East Counter-Terrorism Unit said: "Inquiries are ongoing to establish the circumstances surrounding the incident.
"Given the potential nature of incident and the range of skills and expertise within the North East CTU, the unit is leading the investigation at this time."
Michael Spurr, chief executive of the National Offender Management Service, said: "This was a serious incident and my first thought is with the officer who was taken hostage – we will do all we can to help him recover from this experience."
Her Majesty's Chief Inspector of Prisons, Nick Hardwick, said more Muslim and other minority prisoners at the jail felt they were not treated with respect by staff, compared with white inmates.
A report published by Full Sutton's independent monitoring board hinted at tensions between Muslims and other prisoners when it was published earlier this year.
It said: "Despite the positive efforts of the management team to meet their legitimate concerns, there is still a perception among some Muslim prisoners that there is prejudice against them and that they do not receive the same treatment as prisoners of other faiths.
"However, prisoners of other faiths have complained that their needs are neglected and that Muslim prisoners are favoured."
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