Paedophiles are stealing innocent Facebook family snaps to put on their own depraved pages on the social network.
The perverts trawl the site copying pictures parents have taken of their children and images youngsters have shared with friends.
Then they use them to connect to other child abusers around the world who post sickening comments underneath the snaps.
A Sunday Mirror investigation has uncovered paedophile Facebook pages packed with hundreds of pictures ranging from children as young as eight on beach holidays to “playful” underwear pictures posted naively by schoolgirls in their early teens.
Sprinkled among them were child abuse images on a string of pages with titles such as ‘Lolita’, ‘Jailbait-cuties’, ‘Naturalist kids lovers’ and ‘cute and gay boys’.
Following our investigation, last week Facebook closed down several pages and links.
We were contacted by a worried mum and dad of three children who stumbled across some of the galleries after following the Sunday Mirror’s investigation into paedophiles on Twitter.
Our investigators uncovered even more pages and pictures.
We then reported our evidence to the Internet Watch Foundation and called in child protection expert and former policeman Mark Williams-Thomas to analyse the galleries.
He revealed many of the cunning perverts stay one step ahead of the authorities by using stolen family and teen pictures which could not be classed as child porn.
“I have no doubt these pages have been created by paedophiles,” said Mr Williams-Thomas, who exposed Jimmy Savile as a predatory paedophile in a TV show.
“But they teeter on the edge of criminality so there are pages which are not illegal and Facebook can’t always take them down.
“The problem is that the type of images girls aged 13, 14 or 15 post of them in their underwear is far more difficult to control.
“These pictures end up getting taken and posted elsewhere. Parents must talk to their children about the risks.
“Every parent and child needs to ask this question before they post an image, ‘Are you happy with people not known to you, perhaps even a child sex offender, viewing your image?’
“If you are happy with it then go ahead and post it. If you are not then don’t.”
The couple who contacted us about the disturbing pages – civil engineer Anthony Hemsley, 40, and partner Alex Blue, 36 – started looking for them after being warned by other parents.
They were shocked to find evidence after only a few minutes searching Facebook.
Anthony, of West Sussex, who has two girls aged four and nine and a boy aged six, said: “There were some that looked posed, mostly of half- naked children. They were mainly in their pants.
“But others looked like they were simply taken by families who have put up pictures online of their kids at the beach, holidays snaps and things like that.
“Then they get copied on to these pages which are basically just galleries of under-age children with people perving over them and then putting lewd comments next to them.
“I feel people have been naive in putting family snaps on Facebook, and thinking nothing of it.
“There could be someone harvesting the photos and using them to satisfy their urges.
“I’m anti-censorship, but there should be safety measures in place to protect people.”
Many of the paedophile comments on the posted pictures are too shocking to publish in a family newspaper.
Alongside one picture showing a girl aged about 13 sitting in jeans and vest, one pervert wrote: “more like this without those jiens (sic) haha”.
Under a picture of two girls aged about 14 in shorts and vests, one paedophile posted: “they are both cute but if i had to choose it would be right”.
Another said of a 15-year-old girl: “I wish she was my daughter.” And one commented: “This is why I enjoy teaching… lol.”
Mr Williams-Thomas said the comments served as a point of introduction for perverts from all over the world.
The offenders can then simply contact each other in private messages and arrange to trade images and intelligence away from Facebook, and below the radar of the authorities.
“The pages enable them to talk to other like-minded individuals who come across these images,” said Mr Williams-Thomas.
“They are trying to normalise the sexualisation of children.
“Facebook really have upped their game and are proactively tackling the paedophiles who use the site – but it is a huge task.”
Our investigation comes weeks after Mark Bridger was jailed for the murder of April Jones, five, and Stuart Hazell was sentenced to life for killing Tia Sharp, 12. Both killers had been viewing child porn.
Earlier this week Culture Secretary Maria Miller summoned Britain’s internet firms to Westminster for talks on how to clamp down on online filth.
We handed over evidence, including 52 links to Facebook pages with disturbing pictures and comments, to the Internet Watch Foundation.
The IWF’s team of experts analysed our dossier and discovered that seven of the pages actually contained suspected illegal images of children.
The watchdog, which works with police in the UK and law enforcement worldwide, informed Facebook about the results of the probe and a string of links was closed down on Friday.
Anthony said when he contacted the website they were initially slow to react to close down some of the pages he and his wife had found and was told that certain links “don’t contravene any of their policies”.
But Facebook, which is used by 1.1billion people every month, insists it has many procedures in place to identity dangers online and also reacts to reports from users.
Although bosses admit that it is harder to clamp down on pages which use legal images as a magnet to find other paedophiles.
Report these pages and check your privacy settings
Simon Milner, director of policy for Facebook UK and Ireland, said Facebook was serious about keeping children safe… but it wasn’t easy to control lawful images that attract paedophiles.
He said: “We can act on known illegal images with (monitoring program) photoDNA, take measures and disable accounts – but legal images are harder.
“Although the images aren’t illegal, they are creepy pics of kids and we take action in a way you won’t find elsewhere.
“Once we’re notified, we can remove images and the comments will go as well which means the connection is broken. It’s about disrupting the way these people communicate with each other.”
He urged people to report lascivious pages and for parents to help children change their privacy settings.
Shadow Culture Minister Helen Goodman said: “The evidence is people move to more extreme pornography, sometimes tipping into child abuse.
“This is illegal and, as we saw with Mark Bridger and Stuart Hazell, dangerous.”
Labour MP Ann Coffey said: “A lot of these sites are offensive but aren’t breaking any laws.
“The problem is they are like a honeypot which attract people whose intentions are very bad.”
Siobhan Freegard, founder of parenting site Netmums, said: “Although more research is needed, there is strong anecdotal evidence that abusers may use seemingly innocent images as ‘gateway’ pictures into more disturbing material.
“A good rule of thumb is, if you wouldn’t post it on a billboard outside your home, then don’t post it at all.”