MURDER suspect Paul Northey changed his story when he was quizzed by detectives investigating an attack that left his ex-girlfriend in a coma for six months before she died, a court heard.

The 42-year-old block paver initially said Kathryn Cook had no injuries when he left her at her home in Penshaw Gardens, Stanley, County Durham.

She had suffered a blow to the back of the head, had strangulation marks on her neck and clumps of her hair had been pulled out.

Ms Cook, 44, was found unconscious in her bedroom by her daughter, Rebecca, who was ten at the time, on her return home from school on June 25, 2008.

The jury at Newcastle Crown Court was told that Northey, of Wylam Road, Stanley, initially said: “When I went I did not notice any injuries or nowt on her. Why are you looking at the wrong person who has done this?”

During a later police interview, he told officers: “I pulled her hair. I must have grabbed it. I was trying to keep her at arm’s length. I never ever punched her. She could have banged her head.”

When Northey later admitted grievous bodily harm with intent, he told a probation officer there had been a fight that became physical over a purse he had picked up.

Police were called to Ms Cook’s home on eight occasions in 2005 and 2006.

After dragging her around by her hair on one occasion, he was arrested and cautioned for common assault.

The jury heard the severity and frequency of the violence had increased in 2007.

Friends and family reported seeing her with black eyes, facial bruises, waist, arm and legs, strangulation marks, grab marks, fat lips, lumps to her head and bald patches where he had pulled her hair.

In January 2008, he pleaded guilty to common assault in Consett Magistrates’ Court.

Ms Cook died four days after he was sentenced for grievous bodily harm with intent in January 2009. He was re-arrested and charged with murder.

Toxicology tests revealed Ms Cook, who had a history of problems with alcohol, was five times the drink drive limit at the time at the time of the attack – estimated to have been carried out at 2pm.

Blood samples also revealed Northey had taken amphetamine recently and he told officers he had been “on speed” before the two met in secret. No traces of alcohol were found in his system.

Mr Northey denies murder and the trial continues.