A teen who was on bail for burglary offences when he kidnapped a frail great-grandmother from her care home and raped her has been jailed indefinitely.

Dale Boocock, 19, dragged the 86-year-old from her bed into the garden on September 15 last year.

Bradford Crown Court, West Yorks., heard on Wednesday the details of the shocking attack on the Alzheimer's sufferer who tragically died of natural causes seven weeks after her horrific ordeal.

The court heard that although the attack did not contribute to her death, the judge said it would not have helped her prognosis.

The court heard that Boocock broke into another house after the attack and stole a mobile phone.

Boocock previously pleaded guilty to rape and kidnap, as well as two counts of burglary and one attempted burglary.

He must serve a minimum of four years and nine months before he is considered for release.

He was sentenced to three years for each burglary count, which he will serve concurrently to the indeterminate sentence. He was also ordered to sign the Sex Offenders' Register.