A WOMAN brutally murdered by a cage-fighter had previously worked in Cumbria as a police officer, a court heard.

At Newcastle Crown Court, 50-year-old Paul Robson was this week given a 35-year term for murdering teacher Caroline Kayll, viciously attacked at her home in Linton, Northumberland, last year.

Robson also tried to kill the 15-year-old boy with whom she was allegedly having a relationship, the court heard.

Consumed with jealousy, former prison inmate - who met Mrs Kayll when she was working at HMP Northumberland - launched a terrifying and sustained attack on her on November 15.

He had been blackmailing her over an illegal relationship with the boy.

During his sustained attack, he kicked her in the head while wearing heavy work boots, and may have strangled her. She sustained a catastrophic and unsurvivable brain injury.

On Wednesday, Robson was sentenced at Newcastle Crown Court to life imprisonment with a 35-year minimum.

Passing sentence, Mr Justice Lavender did not accept there was any provocation for the attack, telling Robson: “You were upset when you learned of her relationship but you had known of it for over two weeks when you chose to drive from Glasgow to her home”.

Branded “a cruel and calculating coward” by the prosecution, Robson chopped off Mrs Kayll’s hair in clumps and slashed her.

He also repeatedly attacked the boy with scissors and a meat cleaver.

Nicholas Lumley QC, prosecuting, said: “He was never going to do anything other than ruin her.”

Robson, whose criminal record comprises 92 offences going back 30 years, had denied murder, claiming it was the boy who attacked Mrs Kayll.

The court heard Robson had a clandestine relationship with Mrs Kayll while behind bars in HMP Northumberland.

They lived together but split up weeks before the murder and he blackmailed her after learning of the illegal relationship she had started with the teenager.

She confided in a friend that Robson was blackmailing her for £35,000 and that her ex was “going to ruin her” and tell her school, the jury heard.

Over 10 days in November, she transferred £29,000 to Robson and took out a £10,500 loan, having previously been solvent.

On November 15, Robson drove three hours from Glasgow to Linton, having bought a locksmith’s bar, a magnetic GPS car tracker, screwdrivers, pliers, a wrench and the ammonia which he decanted into a washing-up liquid bottle.

CCTV showed him “prowling” outside her house.

Witnesses heard a woman shout “get out” and later that evening Robson knocked on his former neighbour’s house to say “Caroline was in a bad way”, Mr Lumley said.

He fled to Glasgow and remained at large until tracked down by police after public appeals.

Robson was convicted of murder, attempted murder and blackmail.

He was on the run for six days while his ex-partner’s life ebbed away in hospital.

The 47-year-old, married at the time to a senior prison officer, had started a clandestine relationship with Paul Robson when he was in HMP Northumberland where she taught.

She had previously worked as a social worker, and a police officer in Cumbria before taking on a teaching role behind bars, and then moved into a school role, Newcastle Crown Court heard.

Passing a life sentence with a minimum term of 35 years, Mr Justice Lavender told Robson: “You ended her life and you brought grief and misery to the lives of others.

“Her ex-husband, Ian Kayll, has said that there are absolutely no words to describe her family’s feelings about her loss.”