Eleven members of the same family have been convicted of kidnapping and viciously assaulting a heavily pregnant woman and her partner.

The victims, who cannot be named for legal reasons, were both held against their will and subject to beatings which put the woman in fear of losing her baby.

Those involved in the offences are all related, by either blood or marriage, to Gertrude Frankham, who died in December 2012.

The group, many of whom live in West Norfolk, carried out the attacks believing the couple were responsible for her death, despite medical evidence that she had died from natural causes – a conclusion later re-confirmed following a major police investigation.

Following an extensive investigation led by King’s Lynn CID, defendants were found guilty of offences including kidnap, assault and false imprisonment at Norwich Crown Court and include:

Violet Chilton, 57, of Rands Terrace, Dades Lane, St John’s Fen End, was found guilty of false imprisonment and assault occasioning grievous bodily harm.

Thomas Chilton, 29, Rands Terrace, Dades Lane, St John’s Fen End, was found guilty of two counts of kidnap and two counts of false imprisonment.

Edward Dolan Jnr, 18, of Flower Farm Bungalow, Walpole, was found guilty of kidnap and false imprisonment.

Vanessa Frankham, 48, of Wisbech Road, Walpole St Andrew, was found guilty of kidnap, blackmail and assault occasioning grievous bodily harm. She had previously admitted false imprisonment.

Diane Evans, 18, of Cherry Road, Wisbech, was found guilty of false imprisonment.

A 17-year-old from the Wisbech area was found guilty of kidnap and false imprisonment.

Several members of the group had previously pleaded guilty and therefore did not stand trial. These included:

Laura Ann Dolan, 37, of Two Sisters Close, Sutton Bridge, pleaded guilty to kidnap, two counts of false imprisonment and two counts of unlawful wounding.

Wayne Dolan, 35, of Walpole Marsh, Walpole St Andrew, pleaded guilty to false imprisonment and unlawful wounding.

Edward Dolan Snr, 38, of Walpole Marsh, Walpole St Andrew, pleaded guilty to kidnap, two counts of false imprisonment and wounding with intent.

Sheila Conboy, 55, of Walpole Marsh, Walpole St Andrew, pleaded guilty to two counts of false imprisonment and two counts of unlawful wounding.

Valerie Harris, 47, of Thistlebrook, London, pleaded guilty to false imprisonment and unlawful wounding.

Following Gertrude’s death at the age of 75 in December 2012, members of the family, some of who continued to associate with the victims, became convinced that the male victim had stolen from her.

On 18 April, he was kidnapped and driven to one location by some of the group before being dragged to another where he was viciously beaten - at times with a metal pole and wooden chair - by Wayne Dolan and Eddie Dolan Snr. When he was finally released he sought hospital treatment but, fearing for his life, refused to tell medical staff how he had sustained the serious injuries.

The following day his partner was threatened by Vanessa Frankham and Violet Chilton. In an effort to resolve the dispute, she agreed to meet them on 20 April but was herself then abducted by Thomas Chilton and a 17-year-old boy and driven around by Laura Dolan before being taken to a nearby property.

The group were now convinced her partner was responsible for Gertrude’s death and she was threatened with the death of her unborn child and severely beaten by members of the family, including Sheila Conboy and Valerie Harris, into making a false confession. One of the offenders filmed this on a camcorder. She was left with significant injuries and there were fears for her unborn baby.

During the incident Sheila Conboy phoned police claiming there had been a confession of murder and asked them to attend the property. An extensive and detailed police investigation then began.

As part of this investigation and following the family’s claims in April 2013, an enquiry was launched by the joint Major Investigation Team into the circumstances surrounding the death of Gertrude Frankham. An exhumation took place in May 2013 with a Home Office post-mortem conducted. Following comprehensive enquiries and forensic results, it was concluded that she died of natural causes and there was no evidence to support the murder allegation. She was later reburied.

The eleven will be sentenced at a later date.

Jason Chilton, 27, of Rands Terrace, Dades Lane, St John’s Fen End, was found not guilty of false imprisonment and earlier in the trial Judge Holt had directed the jury to find him not guilty of two counts of assault.

Natalie Jayne Cooper, 22, of Bridge Road, Sutton Bridge, who was charged with false imprisonment saw her case discontinued.