The claims are contained in a controversial new book, extracts of which are published in The Times newspaper.

Bell, who was 11 when she was jailed for the killings of two toddlers in 1968, has been at the centre of a media storm relating to the new book.

She is said to have been offered thousands of pounds for co-operating with the book's author Gitta Sereny.

In the extracts, Bell, now the mother of a 14-year-old daughter, claims that she was subjected to sexual and physical abuse in the years leading up to her crime.

Mary Bell as a child

She says her late mother, Betty, a prostitute specialising in sado-masochism, even tried to kill her.

Bell also claims that men who visited her home, in a tough area of Newcastle, sexually abused her.

But she does not try to excuse her crimes. She admits the horrific abuse meted out at her home was no excuse for her strangling the two young boys.

The ill-treatment continued after her conviction, she says. Her mother told her no-one could be as bad as her and that no-one felt compassion for her.

Bell says that her mother's bouts of abuse were followed by displays of affection. She was given sweets and chips and felt loved by her mother.

Ms Sereny, whose book is titled 'Cries Unheard', tells The Times thart she was so sceptical about the details of Bell's claims that she asked for them to be repeated three times.

Ms Sereny also says that it was Betty Bell's death three years ago that unlocked Mary Bell's silence. She had wanted to "set the record straight", the author said.

Bell had hoped the book would end the media interest in her. Instead the spotlight has intensified, prompting The Times to bring forward its publication of the book extracts.

In a separate article, also published in Wednesday's edition, the newspaper's editor, Peter Stothard, seeks to justify his stance on the story.

He suggests that the book itself provides the best answer to critics who say he should not have serialised it because Bell was paid.