A RETIRED teacher was strangled and robbed by a homeless drug addict who claims he used to have sex with the pensioner for money, a court heard.

George Francis Kidson, 85, died in hospital four days after the attack at his large detached property in Sowerby, Thirsk, North Yorkshire, last November.

Mr Kidson, known as Francis, allowed his killer Ryan Campbell to stay with him on occasions and told relatives he felt sorry for him as he had "fallen on hard times".

The jury at Teesside Crown Court was told on Tuesday that 30-year-old Campbell admits causing the unlawful death of bachelor Mr Kidson, but insists it was an accident.

In a tearful telephone call to his brother, Chad, after the attack, Campbell is said to have said: "He's dead. I'm sorry . . . I've killed an old man down Sowerby."

When police forced their way into the house, Mr Kidson was found unconscious at the foot of his stairs, naked from the waist down with a cut to his scrotum.

A post-mortem examination revealed a number of other injuries, including heavy bruising and broken bones in his neck thought to be from being throttled.

A brain scan showed massive injuries - strokes - "likely to have been caused by application of force to the neck which compromised the supply of blood".

There were also injuries to the victim's mouth which "suggest" a hand was forcefully put over it, and bruises to his left eye, right temple, elbow and finger.

The jury heard a necklace and ring - given to Mr Kidson for his 21st birthday - had been taken, and the finger mark was probably caused by it being removed.

On the day of the attack, Campbell told his mother he had seen the man the family blames for the death of Campbell's father in an industrial accident 20 years ago.

At her home in Thirsk, he armed himself with a knife and told mum-of-four Mrs Campbell "I'm going to get the c***" but he was easily disarmed, and left.

Mrs Campbell called police because she was concerned about his "seriously disturbed" state, and he was stopped nearby, but allowed to go on his way.

Within an hour, he is thought to have got into Mr Kidson's home through a back window, had a confrontation with the pensioner and attacked him before robbing him.

Prosecutor Paul Mitchell told the jury: "This was a cowardly and violent attack on a frail and defenceless man for which there is, in fact, no lawful excuse or mitigation.

"The Crown's case is that Ryan Campbell was in a highly-agitated and aggressive state. Having apparently given up on his original plan, he went to Mr Kidson's home.

"Campbell had a confrontation with the elderly resident at the base of the stairs. He attacked Mr Kidson with blows to the face and chest. He cut him with a bread knife.

"He put his hand forcefully over his mouth, hard enough to injure his mouth, and then strangled him until he suffered a stroke which renders him unconscious.

"He then ripped that ring off Mr Kidson's finger, took the bracelet from his wrist and left. He called his family, but did not call an ambulance or the police."

Unemployed plasterer Campbell, whose address on the court papers is Racecourse Mews, Thirsk, denies murder and faces a trial expected to last seven days.

Prosecutor Mr Mitchell told the jury during his opening address there was no independent evidence of a sexual relationship between the accused and his victim.

He said it was up to members of the panel how they treated the anticipated claims that Mr Kidson paid Campbell for sex and when the alleged arrangement started.

But the court heard how Northallerton-born Campbell - like Mr Kidson - had lived in Thirsk all of his life, and had known the pensioner since a teenager.

The jury was told that Campbell had alcohol and drugs problems, and was haunted by the death of his father, Steven, at a local builder's yard in May 2006.

His family blamed the driver of a dumper truck - someone who had been in the trade for decades - for the accident in which Mr Campbell was crushed between vehicles.

Campbell wept in the dock as his sobbing mother, Julie, recalled the difficulties the tragedy had created in his childhood, and continued to as he grew older.

The jury was given a virtual tour of the home Mr Kidson had lived in alone since the death of his mother 30 years ago, and saw a "body map" showing his injuries.

Mr Mitchell told them: "This case is not a whodunit. In this case there is no dispute it was Campbell who inflicted the injuries which caused Mr Kidson's death.

"Further, the defendant also accepts that he had no lawful excuse to inflict those injuries. The issue for you is whether he is guilty of murder or manslaughter."

The trial continues.