A 58-year-old man who put a young boy through a terrifying sex ordeal has been locked up for the protection of the public.

Repeat offender John Thomas pounced as his 12-year-old victim was walking towards Minster, near Sheerness, on October 6 last year.

Maidstone Crown Court heard that Thomas had heard voices in his head telling him to abduct a child.

Philip McGhee, prosecuting, said Thomas called out to the boy, telling him he wanted to show him something. He then made comments about the youngster’s body and started to molest him.

When he was disturbed by a passer-by, he told the boy to go with him to nearby public toilets.

The boy walked on but was followed by Thomas, who was on his cycle. He grabbed the boy round the waist, pulled him into toilets and in a locked cubicle carried out another sexual assault.

Thomas put a hand over the boy's mouth and said he would see him again at the same place at 3pm. The victim ran home and revealed what had happened.

Thomas, of Kings Road, Minster, admitted liking boys between the ages of 12 and 14 and that he had a problem and needed medical help.

"He said he was afraid of what he was capable of doing," said the prosecutor.

Thomas has 21 convictions for 46 offences stretching back more than 40 years. The first was for gross indecency with a child in 1960. He had served various prison sentences.

Mr McGhee said Thomas was in December 1996 jailed at Croydon Crown Court for sex offences involving young boys.

He was released on licence in August 2002, but was recalled to serve the sentence in full. He was freed in August 2005 and committed the latest offences two months later.

Thomas admitted two charges of sexual assault on a child and one of abduction. He also admitted breaching a sex offenders’ order by failing to notify police of a change of address.

Robert Flach, defending, said reports made it clear that a hospital order under the Mental Health Act was not appropriate.

"There are cases where it is difficult to say anything in mitigation and it would be foolish for me to pretend otherwise," he said. "I cannot argue against a sentence for public protection."

Judge Andrew Patience, QC, said if he had passed a determinate sentence, it would have been six years imprisonment.

He told Thomas that he would have to serve two years and four months before he would be considered for release.

"Your record is an appalling one," the judge told Thomas. "I am satisfied that there is a significant risk of you committing further offences and that there is a significant risk of harm to the public."