A fatal fire that killed six children from the same family was deliberately started by someone pouring a "substantial" amount of petrol through the letter box and lighting it, police said today.
At a brief emotionally charged news conference the distraught parents of the siblings, who were aged between five and 13, repeatedly broke down as they spoke for the first time to thank emergency services and rescuers for their efforts in trying to save the children.
Mick and Mairead Philpott, survived the blaze which was started in the early hours of Friday morning on the ground floor of their council house in Allenton, Derby.
The children died of smoke inhalation. They were asleep upstairs at the three-bedroom house, which was fitted with hard-wired smoke detectors. The couple are understood to have been downstairs.
Smoke from the fire is believed to have rapidly funneled upstairs giving the children no chance to escape or for anyone to reach them alive.
Mr Philpott, an unemployed father of 17 children, has regularly appeared in television programmes and newspapers as a supposed symbol of Britain's welfare benefits culture.
Detectives are investigating whether the attack was the result of a personal grudge against him and his family or linked to his wider "celebrity" in the media.
A 28-year-old woman and 38-year-old man, both from Derby, who were arrested in connection with the blaze have been released without charge.
Assistant Chief Constable of Derbyshire Police, Steve Cotterill, said whoever lit the fire would have known that children were most likely asleep inside.
"It is common knowledge in that community if not nationally that Mr and Mrs Philpott lived there with a large number of children," he said.
Police are urging anyone who finds a discarded petrol can, forecourt staff, or anyone who saw someone carrying fuel at the time of the tragedy to come forward.
Mr Cotterill said the investigation was proceeding well but would take some time. He said whoever was responsible for the fire should examine their conscience and hand themselves in.
Jade Philpott, 10, and brothers John, nine, Jack, seven, Jessie, six, and Jayden, five, all perished in the blaze, while Duwayne Philpott died of his injuries in Birmingham Children's Hospital at the weekend with his parents at his bedside.
Mr Philpott said the family had donated Duwayne's organs to help save the life of another child. He also thanked members of the local community and people from across the world for their support since the tragedy.
"We grew up in a community that's been through a lot of problems with violence and to see this community come together like it has, it's too overwhelming," he said.