A bitter husband whose attempts to kill a Tadcaster man ended in the deaths of two young sweethearts was today starting a life sentence.

Jeffrey Jackson, 37, began plotting his revenge after discovering that his wife had resumed an affair with Tadcaster man Steven Stanger, seven months after claiming to have ended it.

The father-of-three, whose attitude hardened towards his wife when his own five-year relationship with a work colleague finished, told Mr Stanger he would return to avenge his wife's infidelity.

During the three-week trial at Leeds Crown Court, the jury heard how Jackson went about the attack, planning the fire and disposing of incriminating evidence which implicated him.

Leaving work two hours early, he drove to the house in Normanton, West Yorkshire, and squirted petrol through the letterbox of Ash Gap Lane, where Mr Stanger had been living as a lodger, before striking a number of matches to set the hallway alight.

As the flames raged through the three-bedroom house during the early hours of April 12 last year, Jackson's intended target leapt to safety from an upstairs window.

But James Murphy, 28, and university graduate Jane Pemberton, 23, had no way out, and their bodies were later recovered by firefighters, huddled together in the corner of a bedroom. Three weeks later Jackson was arrested and charged with double murder and attempted murder.

Jackson, of Sharlston, Wakefield, stood impassively in the dock as the foreman of the jury returned the unanimous verdict.

The grieving relatives of the young couple embraced each other and began to cry.

Sentencing Jackson to life imprisonment Mr Justice Owen said: "This offence was pre-planned. You went to Ash Gap Lane with murderous intent, equipped yourself with petrol to use as an accelerate, and then cold-bloodedly set fire to the house by pouring petrol through the letterbox and igniting it.

"The fire rapidly became an inferno, cutting off any escape."

As he was led away, Jackson looked over towards the jury and said: "I hope you can sleep."

Updated: 14:46 Wednesday, April 11, 2001