Katie Down, of Topsham, near Exeter, has been living with the man for about six months.

Her mother, Sarah, 34 , says she is furious the police and social services have taken no action to halt the relationship.

A spokesman for Devon and Cornwall police said they could not arrest anyone for simply not wanting to go home.

They also could not act on a complaint of unlawful sexual intercourse unless it came from the girl.

Safe and well

If a girl of this age was reported missing, they would try to find her.

They said they know she was safe and well on Wednesday last week.

Councillor John Smith, responsible for children's social affairs and health at Devon County Council, said social services had no more power than the parents in these situations.

He said: "We do liaise with the police and if they feel that there is a criminal offence that has been committed, then it is up to them to work with the offender in whatever way they see fit.

"It would then be up to us to work with the person who has been offended against."