Derbyshire police say they have 'never come across a crime like it' after two teenagers pleaded guilty to conspiring to kidnap three babies.
The girls, aged 17 and 18, were arrested after a mother contacted the force on September 21 last year.
She told officers a young woman had been to her house claiming to be a social worker. She said she needed to take her baby away for a medical check but the mother became suspicious and refused.
The investigation revealed that the pair had tried to kidnap two other babies in the same month - one in Wolverhampton and one in Huddersfield.
The girls set up fake profiles on Facebook and used them to contact mothers, offering free baby clothes. Police believe this was a ruse to get their addresses and contact details.
Detective Sergeant Duncan Gouck, of Derbyshire police, said: "From the moment the older girl was arrested she told officers she was pregnant but as time went on we realised she was faking this.
“We can’t be clear of the motive in this case but we believe her intention was to get a baby which she would have pretended to have been her own.
"This case was unique to us in its nature and seriousness. We have never come across a case like it.”
The 17-year-old is from Wolverhampton and the 18-year-old is of Evesham. They pleaded guilty at Derby Youth Court and will be sentenced in May.