TWO killers serving life sentences at Whitemoor Prison – including a psychopath from Norwich - are beginning extended sentences for knifing a fellow inmate in a row over some stolen chicken.

Dean Cullen, 24, and Dean Agbegah, 44, were already serving life sentences for murder when they hatched a plot two years ago to attack a long-serving inmate on B-Wing.

Armed with a blunted knife and a potato peeler, the pair followed the victim into his cell when he returned from having a shower. They attacked him, stabbing him a number of times including to his eye, throat and back.

The peeler snapped during the stabbing, while the knife was still lodged in the victim's back as he went to get help.

He managed to stagger out of his cell after Cullen and Agbegah left and was taken to Peterborough District Hospital where he was treated for life-threatening injuries.

The handle of the peeler was discovered by prison staff wedged between pipes behind the wardrobe in the victim's cell. Agbegah's blood-stained clothing was found in a wash bag in his cell.

Cullen, who was jailed for life in 2006 for punching, kicking and stamping a man to death in Norwich, and Agbegah, who was given a life sentence in 2005 for strangling his sister in London, were both charged with attempted murder.

Both were cleared of that charge but convicted of grievous bodily harm with intent following a three-week trial at Cambridge Crown Court.

Today Cullen was given a five-year indeterminate sentence while Agbegah was sentenced to six years indeterminate - both to run concurrent with their life sentences. The sentences will impact on their parole date.

Detective Sergeant Matt Swash said: 'This was a brutal attack where both men set out to cause a great deal of harm to the victim.

'He was stabbed a number of times and had severe defence wounds to his arms as he tried to protect himself. His injuries were horrific and it is only through sheer luck that he managed to survive.'

All three inmates are now serving their sentences at separate jails.

A psychopathic killer jailed for beating a man to death, failed to have his minimum prison term cut on appeal.

• Dean Cullen pleaded guilty in 2007 to the murder of David Lucas, 31. He had repeatedly stamped on his victim's head and thrown his body into the River Wensum.

Mr Justice Calvert-Smith ordered Cullen of Lawson Road, Norwich, to serve a minimum prison term of 20 years.

Lord Justice Hughes referred to Cullen as having a 'psychopathic personality order' when he later dismissed an appeal.