A prisoner who attacked Soham murderer Ian Huntley and strangled another child killer has been given a second life sentence.
Armed robber Damien Fowkes, 36, who was already serving a life term, slashed Huntley's throat in Durham's Frankland Jail in March 2010.
He also strangled child killer Colin Hatch with strips of bedding at Full Sutton Prison near York in February.
A judge at Hull Crown Court said he must serve a minimum of 20 years.
Mr Justice Coulson expressed concern about the attacks within high-security prisons and called for an "urgent review".
He said: "It is troubling that these two attacks were carried out in two different high-security prisons.
"Whilst everyone is acutely aware of the costs of monitoring vulnerable and high-risk prisoners, from what I have seen in this case it appears that the management systems currently in place require urgent review."
The judge said that the "notoriety" of the two victims had no bearing on the sentence.
"Whilst I am aware that the view has been expressed in some parts of the press that the killing of Colin Hatch and the attempted murder of Ian Huntley were somehow lesser offences - deserving lesser sentences - because of the crimes that they had themselves committed, such a view is manifestly wrong, both as a matter of common sense and as a matter of law," he said.
"For the avoidance of doubt, can I stress that that would be so whether the Human Rights Act were in force or not."
Fowkes, from Northampton, had admitted Hatch's manslaughter on the grounds of diminished responsibility and attempted murder over the attack on Huntley.
He used a homemade weapon to attack Huntley, who is serving a life sentence for the murder of 10-year-old schoolgirls Holly Wells and Jessica Chapman in 2002, while Huntley was working on the healthcare wing.
The court was told the attack caused a "severe gaping cut to the left side of his neck".
Prosecutors described how Fowkes, who the court heard showed "strong psychopathic traits", chased Huntley around the healthcare unit at the jail, brandishing a weapon.
At one point Fowkes trapped Huntley in a room but the Soham killer managed to escape by throwing a bedside table at Fowkes as a prison officer challenged him.
The attack ended when Huntley shut himself in a servery as Fowkes tried to get at him and prison guards arrived.
Huntley was in hospital for three days and needed 21 stitches.
When told he had not killed Huntley in the attack, Fowkes said: "I wish I had."
Following the attack, Fowkes was moved to Full Sutton Prison, where he then attacked Hatch.
The court was told Hatch, 38, of north London, was killed while serving a life sentence for murdering a seven-year-old boy while on parole for a previous child sex attack.
Three psychiatrists and two psychologists have examined Fowkes and agreed he has a "deep-seated disorder of great severity".
The judge said he was too dangerous to be placed in a secure mental hospital with other prisoners of a similar nature to Hatch and Huntley.
A Prison Service spokesman said: "Security procedures are constantly reviewed as a result of every serious incident.
"As with every death in custody, a thorough, independent, investigation by the Prison and Probation Ombudsman will take place.
"Prisons take the responsibility of keeping prisoners, staff and visitors safe extremely seriously.
"The management of violence and its reduction is central to successful prison management.
"Strenuous efforts are made to learn from each death in custody or incident of violence."
The Ministry of Justice said there have been only two murders in high-security prisons in England and Wales since 2004 - Colin Hatch and Mitchell Harrison, who was found dead in a cell at Frankland on Saturday.