A convicted murderer who raped a 10-year-old boy while out on licence has been jailed for life.
Stephen Ayre was told he will spend the rest of his life behind bars
Stephen Ayre, 44, of Bingley Road, Shipley, had admitted attacking the boy at a flat near Saltaire in February.
Ayre was originally jailed after the body of Irene Hudson was found battered to death in Shipley in 1984. He was released on licence last April.
He was sentenced on Wednesday at Leeds Crown Court having earlier admitted two rapes, abduction and a sexual offence.
Prosecutor Gavin Howie said Ayre approached the victim in the street and lured him back to a flat where he threatened to slash the child's throat with a Stanley knife if he did not do as he said.
"He prevaricated at first at the door of the flat," he said. "He then physically picked him up and dragged him into the flat."
The court was told Ayre had a psychopathic disorder but not a mental illness.
In police interviews he admitted he was out on licence but wanted to get back to jail. Mitigating, Michelle Colborne said Ayre was deeply sorry for what he had done.
But the court heard how shortly before he was jailed in 1985, Ayre was given a suspended sentence for having underage sex with a girl.
Sentencing, Mr Justice Tugendhat said Ayre had committed very serious offences and posed a particular risk to young people if he was ever allowed back into the community.
"You do not understand the gravity of what you have done," he said.
"You are extremely dangerous and a particular risk to children and young people and other vulnerable people of both sexes.
"I have no doubt there is a high risk you will commit other serious and violent offences if you were free to do so."
The judge said because of that risk he would not set a minimum term and ordered Ayre to be imprisoned for life.
After the case, West Yorkshire Probation service said public protection was its highest priority.
"On the rare occasions when something as serious as this happens, our priority is to identify what can be learnt in order to work more effectively in the future.
"In line with our public duty, we work with the police to do everything we reasonably can within existing resources to reduce the risk posed by offenders with a history of serious offending.
"However, it is impossible to eliminate risk altogether, and the offender must ultimately shoulder responsibility for his actions."
The case has once again highlighted concerns about criminals re-offending while on probation.
Home Secretary Charles Clarke wants those on probation to face tougher supervision to prevent them committing further crimes.
It follows cases such as the murder of Reading teenager Mary-Ann Leneghan in May, where four of those convicted for her killing were under supervision.