The shell-shocked family of a heart bypass patient are demanding a new inquiry into her death, claiming that vital new evidence failed to come to light during an inquest.

Janet Thornton's family yesterday criticised West Yorkshire police for failing to carry out a "full and proper inquiry'' and are calling for a meeting with the chief constable.

Coroner Roger Whittaker recorded a verdict of accidental death on 54-year-old Mrs Thornton, of Denby Road, Woodhouse, Keighley, who died from a head injury at Leeds General Infirmary February last year. But, after the Bradford hearing, her son Christopher Thornton complained that two witnesses who the family believed were "paramount" to the investigation had not been called to give evidence.

Mr Thornton said: "What the family wants is to make an appointment with the chief constable of West Yorkshire because we are going to get another police force to investigate this matter.''

Last night, a West Yorkshire police spokesman said: "Any complaints about the police side of the inquiries will be investigated."

Mr Thornton asked the coroner to adjourn the inquest so that they could hear from these witnesses but Mr Whittaker decided to carry on.

Mr Whittaker said he was satisfied that Mrs Thornton's injury occurred when she fell in a bedroom while staying with her partner's relatives in Kent. The hearing heard how Mrs Thornton banged her head on the floor during a row over an affair which her boyfriend had recently had. The couple then left to return to Keighley.

Mr Whittaker noted that Mrs Thornton had also suffered a fractured bone in her neck but it was not believed that it had caused or contributed to her death.

A post-mortem examination revealed bruises on her body but her boyfriend Steven Walker denied causing them.

Mr Thornton said that the family had endured other tragedies including a brother who suffered a brain tumour and a sister who has cancer.

"In this family it has been one tragedy after another. It's mental torture we have been through."

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