A TEENAGE rapist has been let out of jail after serving just three weeks, because he's deemed "vulnerable" in jail.

The families of children he abused are now terrified they will run into them in their local village, according to Mail Online.

He attacked two kids, a boy and a girl, during warped "murder in the dark" games.

The sicko, now 18, was sentenced to a year, slapped with a restraining order and made to sign a Sex Offender's Register.

But the parents, in the Devon area, were horrified when he was let out after just three weeks inside.

They say the justice system has "utterly failed" them after the "nightmare abuse.

A judge said the man, who cannot be named for legal reasons, has caused "untold damage" to the kids.

He abused them while he was aged 13 between 2013 and 2014.

But it is believed the abuse may have taken place over 18 months.

On September 7, the year long sentence in an adult prison and year-long rehabilitation order was overturned on appeal.

Family of the victims live in the same village as the attacker, according to the news site.

A mum said: "It was of the worst kind of abuse in the end. He got progressively more brave as the weeks went by.

"It was a weekly occurrence. We were close friends with his parents and we would often take turns for meals at each others' houses.

"The children would go off and play Murder in the Dark. Unbeknownst to me he was individually taking the children away and carrying out his abuse."

The kids broke down and revealed the abuse after the boy had a sex ed class at school.

His hysterical sister then also admitted she had also been attacked.

The mum added: "This is someone who encited my five year old daughter who believed in the tooth fairy – into doing sexual acts and keeping it a secret

"He took her innocence – he has left them with life trauma – he does three weeks in prison. It makes no sense."

MailOnline says the appealed decision was not made public.

The boy admitted raping a boy and girl under 13, and other sexual offences in court.

District Judge Diana Baker handed him a two year detention and training order, half to be served in an adult prison before being released under supervision.

But the CPS reduced it, citing his vulnerability in jail.

A spokesman said: "The appeal was allowed because of the defendant’s age at the time, his lack of re-offending in the last five years, the willingness he has shown to work with a youth offending team and his vulnerability in an adult prison.

"Sentence of 2 years detention training order replaced with a 12 months Referral Order with community requirements."

A parent said: "He was immediately released on Friday– and was at a party on a Saturday night.

"I had to warn them they might see him – they are frightened. It effects what we do and where we go."