Andrew Griggs guilty of murdering pregnant wife in 1999

Debbie Griggs was devoted to her three sons, the jury heard

A man has been found guilty of murdering his pregnant wife and disposing of her body 20 years ago.

Debbie Griggs has not been seen since she disappeared from the family home in Deal, Kent, on 5 May 1999.

Jurors at Canterbury Crown Court rejected Andrew Griggs's claims that his wife, then aged 34, had walked out on him and their three young sons.

Griggs, of St Leonards in Dorset, was convicted of her murder and will be sentenced on Wednesday.

The body of Mrs Griggs has never been found.

Andrew Griggs will be sentenced on Wednesday

Prosecutor Duncan Atkinson QC told the court Griggs, a keen sailor, had killed his wife at their home in Cross Road, before burying her body or disposing of it at sea.

Her car was found 1.3 miles away on 12 May with a smear of her blood discovered in the boot.

The court heard Mrs Griggs believed her husband was having a "sexual relationship" with a 15-year-old girl and would have been entitled to half of the family's fishmonger business if they divorced.

Giving evidence, the girl, now aged in her 30s, told jurors she had been groomed by Griggs while in a vulnerable position.

During a two-decade campaign for justice, Mrs Griggs's family and friends maintained she would never had abandoned her children.

Her best friend Helen Cheeseman said she was "overcome with emotion" after learning of the guilty verdict, adding: "It's been a long time coming and finally the truth has been told."

Mrs Griggs's mother Patricia Cameron, who led the campaign, died in January, just weeks before Griggs was charged with murder.

Mrs Griggs's car was found unlocked with a smear of her blood in the boot

Griggs told the jury his wife experienced post-natal depression and "dark moods" after the birth of their three sons.

He said she had repeatedly threatened to walk out and on more than one occasion had told their children: "I might as well go and kill myself."

But Mrs Griggs's GP Dr Peter Schouten told the jury she had "displayed none of the signs or symptoms of depression" in the weeks before her disappearance.

Mr Atkinson said Griggs had been "seeking to blacken Debbie's name".

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Det Ch Insp Kaye Braybrook said Griggs had "proven himself to be a callous and manipulative individual who has gone to great lengths to destroy his wife's reputation".

"For 20 years he has heartlessly carried on with his life while Debbie's family and friends have struggled to come to terms with their loss, and having never had the chance to bury her body and say their proper goodbyes," she said.

"Only Andrew knows how he killed Debbie and what he did with her body, and I appeal to him to have the courage to speak up and enable those who continue to grieve her loss to have some form of closure."