Arthur McElhill killed his partner and five children in the blaze
Convicted sex offender Arthur McElhill killed himself and his family in a house fire in Omagh, County Tyrone, a coroner has ruled.
Coroner Suzanne Anderson said McElhill burned the house down because his partner, Lorraine McGovern, threatened to leave him.
McElhill, Ms McGovern and their five children died in the blaze at Lammy Crescent in November 2007.
He had been having sex with a 16-year-old girl in the weeks before the fire.
"I am satisfied on the balance of probabilities that Arthur McElhill and Lorraine McGovern had been up all night and that she was about to leave, taking with her at least some of her children, when the fire was started by Arthur McElhill," said Ms Anderson.
However, the coroner said she could not prove conclusively that McElhill had intended to commit suicide, noting that he had broken an upstairs window in an apparent bid to escape the home as the blaze took hold.
The coroner said that McElhill and Ms McGovern had gone out on the evening before the fire and left their children in the care of the 16-year-old girl he had been having sex with.
Ms Anderson said that when they returned a neighbour heard McElhill shout to McGovern that she couldn't run.
She concluded that Ms McGovern was likely to be in the process of leaving him and this, coupled with his fear of facing prison because of his illicit relationship, contributed to him starting the fire.
The inquest also heard of McElhill's previous suicide attempts and his use of a Bebo social-networking account in his son's name to groom teenage girls for sex.
It also heard he had two previous convictions for rape.
The evidence that his wife was planning to leave included five full bottles of baby milk which were found in an upstairs bedroom.
Detective Chief Inspector Scott had told the inquest: "I don't think it was for one night. It would be inconceivable that they would need so much milk."
In a statement released after the verdict, McElhill's parents said their lives had been "devastated and shattered".
The McGovern family's solicitor read a statement on their behalf
"Our pain is immeasurable and it will endure for the rest of our lives," they added.
Outside Omagh Courthouse, a solicitor speaking on behalf of Ms McGovern's parents, Theresa and Kevin, said the couple were relieved the proceedings had concluded.
"We are mindful that the McElhill family have also suffered greatly and we extend to them our sincere sympathy," the statement said.
They also paid tribute to the firefighters and other emergency services who battled in vain to try to save the family.