A man has been sentenced to life in prison for confessing to sex offences that took place more than 20 years ago.
Jason Clint Pettit was a serving prisoner when he admitted the offences in Brecon in the 1990s.
Prison staff alerted police and an investigation began to find the victim, who had not reported the offences but had suffered "decades of trauma".
Pettit admitted charges of rape, false imprisonment and indecent assault at Merthyr Crown Court on 28 May.
Following his confession, Dyfed-Powys Police found a record of a domestic incident between the 49-year-old offender and a woman in Brecon in 1996, but no reports of sexual offences were believed to have been made to police.
'Highly dangerous man'
The victim is now living in another area and was traced by police who put a plan in place to speak to her.
The woman, who has a learning disability, had been raped and kept locked in a house.
She had never reported what happened "through fear of the offender".
Det Con Adam Clark said: "It was likely to be very traumatic for us to turn up and ask her to speak about incidents that she might have put out of her mind for many years, and which she had chosen not to report to police."
Based on her statements, disclosures that had previously been made to a social worker and admissions by Pettit, he was sentenced to life imprisonment to serve a minimum of seven years.
Det Con Clark said: "Pettit is a highly dangerous man, who not only caused physical harm to the victim, but decades of emotional trauma.
"We are pleased with the sentence he has received, and hope it will go some way to assure the victim that justice has been served after all these years."
He added: "I would like to thank the victim in this case for having the strength to talk about incidents that happened over 20 years ago. Her courage has helped to keep a dangerous offender in prison for a significant length of time."