The question mark in the title is because the guardian seem to have changed the details of the report.
The headline was ,
Prison officer 'attacked by extremists'Reports say three prisoners at HMP Full Sutton beat up officer after being asked to pray for Woolwich victim
But if you click on the link it takes you to a much less revealing version
http://www.guardian.co.uk/society/2013/may/28/prison-officer-attacked-hmp-full-suttonPrison officer 'attacked by inmates'A prison officer was held hostage and beaten at an east Yorkshire prison by inmates.
The attack took place at Full Sutton prison on Sunday. A Ministry of Justice spokeswoman said: "An incident involving three prisoners took place at HMP Full Sutton on 26 May from 4.25pm and was successfully resolved at 8.40pm after staff intervened."
The spokeswoman said on Tuesday that two officers were receiving treatment. She refused to comment further, saying the police were investigating.
The Prison Officers Association said it was aware an officer had been held hostage and injured but it was still trying to ascertain the facts of the incident.
The use of ' extremist' and the claim it was due to being asked to pray for the Woolwich victim would heavily suggest an islamic element to the story. Have no other confirmation than that of above but have to say that the suggestion is pregnant with plausibility
UPDATE EDIT
The Guardian has now changed the front page headline to the same as the less detailed on inside