Dominic McKilligan, 19, was jailed for life on Friday at Newcastle Crown Court.

Niall Dickson:"After the verdict each authority denied they were responsible"

The court was told that McKilligan killed 11-year-old Wesley Neailey in his garage. He sexually assaulted him and then killed him with a blow to the head with a wrench.

The government has admitted there were "shortcomings in the way the public authorities handled the care and supervision" of McKilligan.

After the verdict, it emerged that McKilligan had a previous conviction for gross indecent assault against four boys in his home town of Bournemouth, for which he had served a three-year supervision order.

But because of the timing of his previous conviction McKilligan missed being added to the sex offenders register by just one day.

The Department of Health said: "There is deep concern about this tragic case... a review of the case is currently under way and officials are working closely with authorities to make sure that the review is completed quickly, gives a full and honest examination of what happened, and includes independent oversight."

On the steps of the court Detective Superintendent Trevor Fordy, who led the investigation into Wesley's murder, said: "Dominic McKilligan, in my view, was a time bomb waiting to go off."

Judge Mr Justice Bennett, sentencing McKilligan to life for murder and nine years for rape, told him: "You are a dangerous, manipulative, callous paedophile and killer."

The case has prompted calls for changes to the law on sex offenders and for a national network of treatment centres for young sex offenders.

The court heard Wesley Neailey was a "cheerful and affectionate" boy

NSPCC Director of Child Protection, Neil Hunt, said after the verdict: "Dominic McKilligan was already a seriously disturbed boy by 14 years of age.

"He was in local authority care and assessed as a very grave risk to children."

The jury took two hours and 50 minutes to find the 19-year-old guilty of the offences committed in Newcastle in June last year.

McKilligan had gained Wesley's trust in the weeks before, after striking up a conversation in the street.

The 11-year-old would occasionally hang around McKilligan's garage where the student was working on his cars.

On Friday 5 June, Wesley rode on his bike to McKilligan's house. Within an hour he had been murdered.

Dumped body

The prosecution said it was likely the boy was killed after he turned down the student's sexual advances.

After the killing, McKilligan drove to a village on the outskirts of Newcastle and dumped his body in a quiet country lane.

That night he turned up at his part-time work delivering pizzas, though he had tried to get out of it.

Two days after the murder, McKilligan drove his unwitting flatmate along the same country lane he had dumped the boy's body.

He appeared fascinated with what he had done, but never let on to his companion.

As the police search stepped up for Wesley, McKilligan, posing as an ordinary member of the public, would report a sighting of the boy to detectives.

'Tragic accident'

He nearly got away with his crime, but for a tip off from a former care worker three weeks after the murder about his past.

A police search of his house uncovered a cheque made out to Wesley, which linked the student with his victim.

The net closed in on McKilligan in the days to come, and eventually a month after the murder he led detectives to the boy's body.

He maintained his innocence, however, and claimed Wesley's death had been a tragic accident.

Wesley had fallen from the car in McKilligan's garage, he said, after he swung back the doors violently to confront what he thought was an intruder.