The brother of a teenage girl believed to have been murdered by 'the 'Beast of Wombwell' fears he may have killed others.
Peter Pickering died on Saturday after being locked up for 45 years for killing 14-year-old Shirley Boldy in Barnsley in 1972.
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Announcing his death, West Yorkshire Police confirmed that the 80-year-old, who was known as the 'Beast of Wombwell' was expected to have been charged with the murder of another 14-year-old, Elsie Frost, whose body was found in Wakefield in 1965.
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He had also just been convicted of the rape of an 18-year-old woman in the Stocksbridge area of Sheffield in 1972 after luring her into his van and attacking her just a few weeks before he killed Shirley.
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Colin Frost, the brother of suspected victim Elsie, said: "I just feel like we've been cheated now out of getting what we've been trying to get for so long - justice for Elsie.
"And it's just not going to happen now, well certainly not in the way that we wanted it - to have Pickering in court."
Mr Frost, who pushed for the re-investigation of the case three years ago along with his sister, Anne Cleave, said: "It's just an incredible feeling of frustration now.
"They uncovered a monster. The man was such a nasty, nasty piece of work."
Asked if he believed Pickering could have killed others, he said: "I think there's every likelihood.
"If you're asking my opinion, there are other offences. I couldn't say whether it's another rape, another kidnap, another murder. The suspicion at the back of my mind is that it's all of them."
Elsie was stabbed in the back and head as she walked through a railway tunnel in Wakefield, West Yorkshire, in October 1965.
As part of the investigation into her death, detectives looked back through Pickering's conversations with psychiatrists and also found a storage garage he rented in Owlerton, Sheffield, containing possessions including handcuffs and exercise books filled with his rantings.
One note written in 1970 said: "Sex is predominant in my mind - eclipsing all else. Maybe I will be a sex maniac proper. Rape, torture, kill."
Pickering, 80, died at a secure hospital in Berkshire where he was held after he admitted the manslaughter of Shirley Boldy by diminished responsibility in 1972.
Shirley was bundled into Pickering's van as she was returning to Wombwell High School.
He then drove her to a secluded location where he tied her up and raped her.
He tried to strangle her before stabbing her to death.
Leeds Crown Court heard last week how Pickering had convictions for sex offences dating back to the very early 1960s and was in prison from 1966 to early 1972 for a violent sex attack on a teenager.