A nursery worker and two accomplices in Britain have pleaded guilty to carrying out a string of sex attacks on children as young as 18 months old.

Vanessa George, 39, admitted seven counts of sexual abuse and six counts of distributing and making indecent pictures of children.

She committed the crimes at Little Ted's nursery in Plymouth, where she worked.

She denied one count of sexual assault, which was ordered by the judge at Bristol Crown Court to lie on file.

The children in George's photographs have never been identified.

By analyzing electronic references stored within the images, detectives have been able to work out roughly when the pictures were taken.

With the assistance of a consultant paediatrician, they have also estimated the ages of the children involved.

By cross-referencing nursery records, they have narrowed down to 30 the number of families who would have had children of the right age, at the relevant time, in the care of George.

But beyond that, individual identification is very difficult.

Co-defendants Angela Allen and Colin Blanchard also admitted a string of charges relating to assault and child pornography.

Allen, 39, an unemployed single mother from Nottingham, wept in court.

Blanchard, also 39, pleaded guilty to 17 child pornography counts and two sexual assaults on children.

The computer parts salesman, from Rochdale, Lancs, also admitted a further charge of possessing extreme pornography.

Blanchard, who was married and had a young daughter, had been on the sex offenders register.

"The abuse was carried out solely for the sexual gratification of George and her two co-defendants," Sky News West of England correspondent Katie Stallard said.

"The three apparently first met on Facebook last year, but never actually met until they were led together into the dock at Bristol Crown Court. The trio traded thousands of explicit email and text messages detailing horrific fantasies of child sex abuse."

Sky News has also learned George — who is married with two teenage children — even discussed with one of her accomplices the possibility of abducting a child.

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