A former tutor labelled a "predatory paedophile" by British detectives was today handed a indeterminate prison sentence after she admitted sexually abusing young children.
Carol Clarke (aged 46) assaulted children she followed into toilets in Grimsby and other parts of Lincolnshire, she told detectives.
Grimsby Crown Court heard she was sexually aroused by watching young children urinate and from seeing them looking distressed when they needed to go to the toilet.
Sentencing Clarke, Judge David Tremberg told her she would have to serve a minimum of four year in prison.
Judge Tremberg told Clarke, of Cromwell Road, Grimsby, Lincolnshire, she would only be released from prison once parole board members were satisfied she no longer posed a risk to young children or the public.
He told Clarke, who sat motionless while being sentenced: "This is a sad and deeply troubling case.
"From the time you were a very young woman you have had and maintained a very worrying sexual preference, in particular young girls when they are urinating and when they are distressed."
He told Clarke, who won a place at Cambridge University after she had completed her sixth form exams, she was "clearly an intelligent woman" and could have endeavoured not to indulge her interest in children.
At an earlier hearing Clarke admitted abusing young boys and girls, with some of her offences dating back to before 1992.
Gordon Stables, prosecuting, said the case had been brought based on the confessions of Clarke, after she was reported to police earlier this year by a mental health care worker.
He told the court Clarke had confessed over a period of two decades, to various health care professionals, to offences she committed on children ranging from as high as 100 to as low as 10.
Mr Stables said it was difficult to distinguish between fact and fiction but that the Crown believed Clarke had committed dozens of offences.
He told the court Clarke had taken a job in an ice-cream van in order to try to get close to children, and had used events organised by her church to come into contact with youngsters.
He said she had suffered from suicidal tendencies and depression for a number of years but it was only when she was risk-assessed by Dr Joe Sullivan, a prominent psychiatrist dealing with sexual abuse, that he found her to have most likely abused young children.
Clarke is understood to have worked as a part-time college tutor for adult students between 2003 and 2007 but did not teach children.
She was convicted of six of the 12 charges brought against her and the remaining six were ordered to remain on file by the judge.
She was convicted of indecent assaults on children before 1992 and sexual assault on girls under 13 in 2008. Clark was also convicted of being a public nuisance.
Detective Sergeant Stewart Watson of Humberside Police said: "Predatory paedophiles such as Carol Clarke are rare.
"Experts agree that women commit only a fraction of child sexual abuse but as little is known about female offenders, it is difficult to be accurate.
"There are claims that between 5% and 10% of abuse against prepubescent children in the UK is committed by females. However, only about 5% is thought to involve a woman acting alone.
"There are still those members of the general public and even some experts who still ignore women's capacity for sexual abuse.
"Thankfully, education is challenging these beliefs."