Posing as an au pair to families across Europe, a serial pedophile sexually assaulted at least 24 children, including a four-month-old baby.
One of the UK’s most “sneaky” pedophiles used Gumtree to get nanny jobs to rape dozens of children.
Over a period of five years, Aaron McWilliams – whom police have called “any family’s worst nightmare” – sexually assaulted at least 24 children, including a four-month-old baby, after finding work on both networks social and on the Gumtree classifieds site.
Using forged references, the 28-year-old duped families across the UK and all the way to Italy and Germany.
Earlier this month McWilliams, from Northern Ireland, was sentenced to life in prison, serving a minimum sentence of nine years, after being convicted of a series of sexual abuse offenses on children.
And police say there could be more casualties, with Met Police Detective Superintendent Adam Ghaboos saying the case is one of the most serious he has ever seen.
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McWilliams sometimes assaulted more than one child in the same household.
He also encouraged the children to abuse each other. Almost all of his victims were boys.
He was first convicted of abusing a four-year-old in London in 2015. However, the full extent of his crimes was only recently revealed.
Police who arrested him for the second time found nearly 2,500 explicit images on his phone, including images of him abusing young children. Not all the victims have been identified, despite an extensive investigation by Interpol.
Superintendent Ghaboos called McWilliams “any family’s worst nightmare.”
“He is manipulative, cold, calculating and very dangerous for children and young people,” he said. “McWilliams is a predatory pedophile.”
The abuse took place from September 2012, when McWilliams was 20 and lived in Northern Ireland, until March 2017 when he had been in London for at least two years.
He abused children in London, Scotland, the Midlands, as well as other countries in Europe.
Detectives say he created a profile advertising his services as a nanny or au pair.
He is believed to have made extensive use of Gumtree, which has 10 million monthly users, with potential families looking for a nanny having to do their own screening.
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McWilliams was first arrested five years ago on suspicion of assaulting a boy at an address in Southwark, south London.
Officers seized her phone and other electronic devices, but said they were unable to access the content.
He was convicted of the offense in 2016 and reportedly served a relatively short prison sentence.
After his release, McWilliams was placed on a Sexual Injury Prevention Order, prohibiting him from unsupervised contact with children under the age of 16.
Yet in February 2017, a family in Bromley, south-east London, hired McWilliams as a home nanny through Gumtree.
Police say he “slyly forged good character references” to get the job.
Less than a month later, the family’s four-year-old daughter told her mother she had been inappropriately touched.
McWilliams was arrested a second time and jailed for seven years for sexually assaulting a minor in August 2017.
During this investigation, detectives seized another phone belonging to McWilliams.
They found 2,472 indecent images of children, including 326 “Category A” photographs of the most serious abuse.
The discovery sparked a third investigation, which this time covered a much larger geographic area as police attempted to identify as many victims as possible.
Investigators tracked down the families who hired him and found at least 24 victims.
In 2018, detectives confronted McWilliams at Belmarsh Maximum Security Prison and on November 2 he admitted 40 more child sex offenses at Woolwich Crown Court in London.
A 16-page indictment shows he raped a six-year-old boy six times in the summer of 2013.
Another four-year-old boy was raped by McWilliams and repeatedly assaulted in May 2015.
At least one victim has still not been identified by the police and is named in the indictment as “an unknown child … aged one year or less”.
McWilliams was sentenced to life with a minimum sentence of nine years. He may become eligible for parole before he turns 40.
Superintendent Ghaboos said, “Our investigations have led to a large number of McWilliams casualties, but we cannot rule out the possibility that there are more.
“I urge all families who have employed McWilliams or who believe he may have had contact with their children to come forward.”
In a statement, Gumtree said: “We welcome the conviction of Aaron McWilliams for his appalling offenses.
“Our dedicated security team worked with the police as part of their investigation. Gumtree takes the safety of our users very seriously and we are committed to making our site as secure as possible.
“We will continue to work closely with the authorities and encourage all users to report any suspected criminal activity to us so that we can take the necessary steps to remove violators from our site.”
This article originally appeared on The Sun and has been reprinted here with permission