A MAN who battered his lover's son to death in revenge when she jilted him was jailed for life yesterday.

Computer planner Robert Green, 44, phoned mother-of-two Janice Stott, 39, and told her: "You have taken something precious from me. Think what's precious to you."

An hour later, after battering 18-year-old Mark Stott with a hammer, Green rang her back and said: "It's sorted. I have killed Mark."

The murder happened two days after Mrs Stott told Green that she had another lover.

She moved out of their home on Teesside to work for construction firm Taylor Woodrow in Bromley, Kent, and started up an affair with her manager.

Jealous Green crept up behind Mark, a trainee highways inspector, as he sat on a settee, laughing at a TV comedy.

He hit him six times with the heavy duty hammer at their home in Ingleby Barwick, Teesside. Then he slashed his own wrists and neck.

After the second phone call, Mrs Stott phoned ex-husband Stephen Stott, who rushed to the three-bedroom semi-detached house in Cennon Grove, Ingleby Barwick, with Mark's 20-year-old brother, Lee.

They found Mark dying in the living room, and Green bleeding from superficial wounds in a bedroom.

Mrs Stott told a jury at Teesside Crown Court that she finally ended her six-year affair with Green two days before the killing on June 6, last year.

Green, a computer programmer at Newcastle Airport, claimed that Mrs Stott had cancelled their marriage plans twice and he was depressed. He admitted manslaughter due to diminished responsibility, but was convicted of murder.

High Court judge Justice Rafferty told Green: "A likeable, innocent lad has had his life cut short by your brutal attack. His mother, upon whom you were taking revenge over her rejection of you, will never recover from her loss.

"Mark's father and brother saw the scene of misery you had caused when you silenced him. After the first blow with a heavy weapon, he must have been helpless.

"It was a wicked attack and you have caused great heartbreak, but I accept your genuine remorse."

There were tears among Mark's family and friends in the public gallery as the jury foreman announced the verdict of guilty to murder.

After the trial, the victim's brother, Lee, said: "Although we feel victorious, we don't feel like winners, there are no winners in a situation like this.

"Nothing is going to bring Mark back. We just want to put this behind us."

Detective Sergeant Michael Wilson said: "This was an horrific incident in which Mark was killed to satisfy Robert Green's revenge.

"I hope the verdict will help the family cope with their tragic loss and let them get on with their lives."