The investigation is expected to find that cases of sorcery-related abuse are now spreading outside the capital to areas such as Liverpool, Newcastle and parts of Yorkshire — although they remain confined to only a minority of Africans in Britain.

The abuse of the children has ranged from shouting to beating, starving, slashing with knives and razors and, in at least one case, murder.

Lord Adonis, the education minister, announced in the House of Lords last week that the report, which he said addressed “very grave” issues, was likely to be published by next month.

The education department maintains that publication of the findings, which were delivered to Whitehall in January, has been delayed because they are being “studied by ministers”.

Critics insist the real reason is that the government is fearful of upsetting race relations. “They have found this quite hot to handle,” said Richard Hoskins, visiting research fellow in the sociology of religion at King’s College London and an expert witness in several court cases involving witchcraft claims.

“I think it is almost as crude as white, liberal, middle-class people thinking they can’t be seen to be telling black people what they are doing wrong. It is ridiculous when you are dealing with children’s rights.”

Debbie Ariyo, founder of the lobby group Africans Unite Against Child Abuse, said that while many abuse reports had been exaggerated, “we can’t shy away from the problems”.

Among the cases expected to be covered by the report are:

• Adam, the name given to a boy whose torso was found in the Thames in 2001. The killers of the child, who is believed to have come from Nigeria and to have been a victim of ritual sacrifice, have not been found.
  
  
• Girl B, a case which came to court last June in which three people were given sentences ranging from four to 10 years for torturing a girl of eight from Angola who they believed was a witch. Part of the “exorcism” involved rubbing chilli peppers into her eyes, a practice Hoskins described as a “repeat pattern in many cases”.
  
  
• Cases in which British-born children have been sent to live in Congo and ended up in revivalist churches where they were subjected to brutal exorcisms.

  Practices such as the exorcism of evil spirits from the “possessed” were first noted in Britain shortly after large numbers of African immigrants began arriving in the 1990s.

  People from several countries have been implicated, but many allegations centre on evangelical churches in the Congolese community.

  About 20,000 immigrants from the Democratic Republic of Congo live in Britain, mainly refugees from the country’s devastating civil war, which has cost an estimated 4m lives since the 1990s.

  Activists who have investigated witchcraft in Congo argue that before the 1990s, such abuse of children hardly existed. However, with an increase in the number of child soldiers and prostitutes and orphans wandering the streets of Congolese cities, children have come to be blamed for many of society’s ills by a people with a long tradition of believing in the supernatural.

  An investigation last year by Save the Children, the international charity, noted: “Witchcraft and violence against children seems to have been established as a pattern within urban Congolese society. The revivalist churches play a role in amplifying conflicts within the family. They offer no explanation other than child witchcraft.”

  Eleanor Stobart, the consultant who wrote the report, was given access to Metropolitan police case files and held discussions with teachers, social workers and religious leaders over three months.

  She is understood to conclude that while there is little firm evidence that witchcraft- related abuse is widespread, it may be under-reported.

  She is expected to call for greater efforts to integrate immigrants who, in many cases, speak little English and have limited contact with mainstream society.

Explore UK News

• Science News

• Crime News

• Education News

• Health News

• Scotland News

Times Recommends

• Long hours drive lawyers to drugs
• Darling to resist blanket savings guarantee
• £3m appeal to save Vanbrugh's Baroque gem