Caroline Kayll: Cagefighter Paul Robson 'blackmailed and murdered' teacher

Caroline Kayll died in hospital after being attacked at an address in Linton

A cagefighter murdered his teacher ex-partner after blackmailing her about her unlawful relationship with a teenage boy, a jury has been told.

Caroline Kayll died after the "vicious" attack at her Northumberland home in November, Newcastle Crown Court heard.

The 15-year-old boy who was also at the property suffered multiple injuries.

Paul Robson, 50, of Wallsend, denies murder and blackmail, claiming Ms Kayll was killed by the teenager, whom he also denies assaulting.

Mr Robson had started a clandestine relationship with Ms Kayll, 47, while she was a married prison education worker and he was an inmate at HMP Northumberland.

After he was released, and Ms Kayll separated from her prison officer husband, he moved into her home in the village of Linton, near Ashington.

But they split up weeks before the murder when he found out she had started a sexual relationship with the boy, the prosecution said.

The former MMA fighter threatened to expose the relationship and "ruin her" by telling her school, the court was told.

In exchange for his silence, over 10 days in November, Ms Kayll paid him £29,000 and took out a £10,500 loan, prosecutor Nicholas Lumley QC said.

Jurors heard that days later Mr Robson sent a series of messages to their former neighbour about Mrs Kayll's relationship with the boy, saying he was "losing his rag".

Paul Robson ran fitness programmes and his email address began "cageconditioningcoach", the jury heard

On 15 November, Mr Robson travelled from Glasgow to Ms Kayll's home armed with two bottles of ammonia, screwdrivers, pliers and a wrench, the court heard.

She suffered fatal brain injuries, had injuries to her eyes and bruising to her neck which indicated she may have been strangled, Mr Lumley said.

Her hair had been chopped off in clumps and her clothes cut up.

She was placed on life support at hospital in Newcastle but died days later.

Jurors heard Mr Robson had also used a variety of knives to attack the 15-year-old but he survived.

The jury saw footage of Paul Robson at a service station on the M74 travelling from Glasgow towards Linton, Northumberland

Mr Lumley said the defendant was seen on CCTV "snooping and prowling" outside the house and later knocked on a neighbour's door to say "Caroline was in a bad way".

When the neighbour went to the house she saw lots of blood and hair and found Ms Kayll face-down, the jury was told.

She also discovered the boy, who was in shock, vomiting blood and "scared and frightened".

When Mr Robson was arrested he told police he was "hit from behind on my head and back" after arguing with his ex, jurors heard.

"I recall feeling something around my throat ... I remember feeling dazed, sick and scared," he said.

James Mulholland QC, for the defence, cross-examined the teenager suggesting he had attacked Mrs Kayll, which he denied.

The trial - which has been heard throughout the week but can only be reported now after reporting restrictions were lifted - continues.

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