A former senior council officer who posed as a tramp to throw police off his scent while he sexually assaulted a string of schoolgirls was jailed for 13 years today.

Anthony De Boise, 58, a father of two, disguised his voice and wore dirty old clothes as he carried out the assaults on victims aged between 13 and 16 over a period of 11 years.

The distraught girls all told how an apparently uneducated and badly dressed man had struck as they walked along remote paths in Surrey.

In fact De Boise was a former building inspector for Wandsworth council in southwest London who wore a stained tracksuit and dirty trainers before threatening to kill his victims. Some girls had a knife placed to their throats and were ordered to undress. Others were tied up.

In June at Southwark Crown Court he admitted six charges of indecent assault dating back to 1989. He was eventually trapped by DNA evidence.

Today judge Nicholas Loraine-Smith told De Boise that he was sure if the right circumstances arose he could still be a danger to teenage girls. He added that , he agreed with the psychiatrist’s conclusions.

"It looks as though you were simply acting out your sexual fantasies and this fantasy life became more extreme as time went on," said the judge.

"But all the reports I have read about you persuade me that if the right circumstances arose you could well present a continuing danger to teenage girls.

"You followed them into secluded places, you attacked them, you used varying degrees of force, you threatened to kill or rape some of them, you produced a knife on occasions and even tied the hands of one girl behind her back."

De Boise, who was told he would have to serve half his sentence before being considered for parole, was told that upon his release he would have to register as a sex offender for the rest of his life.

Detective Constable Andy Lawrence said De Boise was "a predatory sexual offender who preyed on young and vulnerable children".

He added: "He acted with no regard other than to satisfy his own sexual lust. I am relieved that this dangerous man has finally been caught after a seven-year reign of terror.

"I am happy for the girls involved that justice has finally caught up with their attacker."

During the attacks De Boise hid behind his image as a respected family man from a small Surrey village and was convinced that he had got away with his crimes.

In April last year he was arrested after one of his relatives accused him of stealing money. It was the first time that he had come to the attention of police.

Although the charge was eventually dropped, officers took a DNA sample from De Boise and they found the sample matched the DNA taken from his last two known attacks on two 13 year-olds and a 14-year-old in 1995 and 1996.

Police believe that De Boise may be responsible for more attacks on girls who may have been too scared to come forward.

All of the attacks took place during the day and were within a 20-mile radius of his £500,000 home in Holmbury St Mary, near Dorking. They started in June 1989 and ended in June 1996.

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