Police and child protection experts have now created a training film for all front-line professionals who work with children to teach them how to recognise the signs that a child may be suffering, or likely to suffer harm from witchcraft.

The DVD will be launched at a conference on the subject in London today, organised by the Met police and the Churches' Child Protection Advisory Service (CCPAS), before being distributed to those in the force area who work with children who may be affected.

Detective Superintendent Terry Sharpe, head of the Met's Project Violet which tackles faith-based child abuse, said: 'Abuse linked to belief is a horrific crime which is condemned by people of all cultures, communities and faiths.

'Families or carers genuinely believe that the victim has been completely taken over by the devil or an evil spirit, which is often supported by someone who within the community has portrayed themselves as an authority on faith and belief.'

'But regardless of the beliefs of the abusers, child abuse is child abuse and it is important that professional are clear about the signs to look for.'

At the event at City Hall, detectives will debate with teachers, social workers and healthcare professionals to discuss how to tackle what is now a growing problem in Britain.

In 2004 just two such cases were reported to Scotland Yard.  By 2009 it had risen to seven, and by 2012 it had risen again to 19.

Among this year's 27 reports of such abuse, cases included a child forced to drink unknown substances to 'rid them of evil spirits' and parents removing their children from school and taking them abroad to attend an 'exorcism' ceremony.

One case has already resulted in an arrest for rape, and another in a charge of rape being brought. 

Previous cases dealt with by Scotland Yard include a child having chillies rubbed into its eyes to 'remove an evil spirit' and being cut with a knife for the same reason.