A 15-year-old boy has been locked up for three years for raping a four-year-old while baby-sitting.

The child was raped after waking up while lying on the floor next to the defendant who was watching television.

Barrister, Stephen Couch, for the defendant, said his client still cannot say why he did it.

Neither defendant nor child can be identified for legal reasons.

Prosecutor Michael Wigglesworth, told Bradford Crown Court yesterday the baby-sitting had been a regular arrangement and the victim's mother had put her son to bed as normal when she went out in September last year. When she got back she had sent the defendant home because he had school the next day and then it had become apparent what had happened.

The young child called from his bedroom that he was in pain and it became clear he had been abused.

The defendant denied doing anything wrong but later that night admitted it to the police. At an earlier hearing he pleaded guilty to a charge of rape.

Mr Wigglesworth said the victim had not been the same since the incident.

The court heard the defendant has no previous convictions or cautions. "He's an immature 15-year-old on the dawn of sexual awakening," his barrister said.

Mr Couch said his client had a background of personal problems and would find any detention difficult.

Judge Linda Sutcliffe said the offence was too serious to be dealt with by a community penalty and told the teenager he would have to sign on the sex offender's register.

Ordering he serve an extended licence period of three years when released from detention, she said she was satisfied he represented a danger to the public but the period of detention would have been longer if he had been an adult.

The judge also made a sexual offences prevention order banning the defendant from contacting his victim, from any unsupervised contact with a child under 16 and from working with children under 16.