A 35-year-old prisoner was today being held over the murder of child sex killer Colin Hatch at one of Britain's most secure jails.
Hatch, 38, was told he must serve the rest of his life behind bars after being convicted of killing a seven-year-old boy while on parole for a previous child sex attack.
But he was killed last night at the maximum-security Full Sutton prison near York.
Humberside Police arrested a 35-year-old prisoner on suspicion of murder.
Hatch had a string of convictions for assaulting young boys when he was jailed for the murder of seven-year-old Sean Williams in January 1994.
Jailing Hatch, Judge Nina Lowry said he was "highly dangerous" and told him it was not possible to envisage a time when he could be released safely.
Sentencing him at the Old Bailey, the judge said: "It is not possible today to envisage when you could be safely released from prison and as of today life imprisonment should mean what it says - namely imprisonment for life.
"In my judgment, you should never be released back into the community while there remains the slightest danger you will reoffend."
Unemployed Hatch, then 21, was convicted after the jury of six women and six men deliberated for less than three hours and smirked when he heard the verdict.
Two years previously, he was jailed for three years for assaulting a boy of eight in almost identical circumstances.
His lawyer warned he could kill when he was released.
Within 11 weeks of being paroled in April 1993, Hatch fulfilled that chilling prediction.
Sean was abducted, sexually assaulted and then choked to death after Hatch lured him to his tower block home in Norfolk Close, Finchley, north London.
A postman discovered the youngster's body taped up in bin liners and dumped in a lift.
A year before he was jailed for attacking the eight-year-old, Hatch abused a boy of 10, dragging him into the same lift where he was later to dump Sean's body. He indecently assaulted the youngster.
His murder conviction prompted a review of parole and probation for those convicted of sex crimes, with Sean's mother and father, Lynn and John Williams, saying others had to take some of the blame for their son's death.
They included the parole board, probation service and doctors who treated Hatch in prison.
Speaking at the time, Mrs Williams said: "Never again must a child be murdered by a pervert. Never again must a family have to suffer this experience and never again must Colin Hatch be released back into our community."
Detective Superintendent Duncan Macrae, who led the murder inquiry, described Hatch at the time as a frighteningly cunning criminal. He had pulled the wool over the eyes of the authorities and would kill again if he was ever released.
The two-week trial heard fantasies "involving abduction, sexual abuse and the killing of young children" written by Hatch were found in a wardrobe in his mother's bedroom after his arrest.
Hatch had a string of previous convictions from the age of 15 for attacks on six young boys.
At his previous trial for indecently assaulting the eight year-old boy and choking him until he lost consciousness, psychiatrist Dr Anthony Wilkins recommended that Hatch was a "menace to the public" and should be sent to Broadmoor top security hospital.
But Broadmoor had not considered Hatch dangerous enough at the time, Dr Wilkins said. Instead he was jailed for three years, as the judge was given no alternative.
The last unannounced inspection of Full Sutton jail, carried out in November 2007, found the prison was a "commendably stable and largely safe environment".
"The security department was well staffed and impressively organised," the inspectors said.
"The work of the intelligence unit was particularly noteworthy.
"Security impacted across the establishment, but it was generally proportionate to prisoner risk. Despite some complaints from prisoners, categorisation and allocation arrangements were appropriate."Reuse content