Shahid Mohammed, 37, was yesterday found guilty of killing five children and three adults in the blaze at the property in Birkby, Huddersfield, in 2002, following a five-week trial at Leeds Crown Court.
Mohammed had been investigated by police at the time but skipped bail and fled to Pakistan prior to a 2003 trial in which several other people were convicted for their involvement in the incident.
During his trial, jurors heard that the blaze which caused the deaths of eight members of the Chishti family had followed a grudge that the defendant had been “pursuing vigorously”.
Prosecutors said Mohammed, of no fixed address, reacted angrily when his sister, Shahida, became involved in a relationship with a man named Saud Pervez, of whom he did not approve.
Jurors were told that petrol bombs were thrown into the property in Osborne Road, while petrol, believed to have been poured into the home through a nozzle, was ignited.
During the trial, one surviving member of the Chishti family, Siddiqah Aziz, told how she managed to save her father, Abdul Chishti, from the inferno, but was prevented from coming to the aid of other family members when she was met by a wall of flames.
He added: “This incident remains the biggest single event of multiple murders that West Yorkshire Police has investigated.”
Bearded Mohammed, who stood in the dock wearing glasses, a striped shirt and a dark tie, showed no emotion as he was found guilty of eight counts of murder and one of conspiracy to commit arson with intent to endanger life.
He will be sentenced at Leeds Crown Court today.