The deaths of six children in a house fire in Derby started by parents Mick and Mairead Philpott 'could not have been predicted or prevented', a serious case review has found.
The Philpotts were jailed in April last year for the manslaughter of their children Jade and her brothers John, Jack, Jesse, Jayden and Duwayne, who were aged between five and 13.
A report into the tragedy said professionals in contact with the family could not have foreseen the couple's plot to set the house on fire in a bid to frame Philpott's former mistress who had left the family.
A statement by the Derby Safeguarding Children Board said: "The tragic deaths of the children could not have been predicted or prevented.
"Given the notoriety of the father, the incidents of domestic abuse and visibility of the children, there were some opportunities to get to know the family better, although this would not have led to professionals becoming aware that there were plans to deliberately set fire to the house when the children were sleeping."
A serious case review into the 2012 fire found that the living arrangements at the house were 'unorthodox and not one that professionals often come across' because prior to the fire, Mick Philpott had lived at home with his wife and his former mistress, along with their 11 children.
At the time of the blaze he lived in the Victory Road council house with just his wife and the six children who perished in the fire. It said that agency checks not long before the fire would have revealed 'happy, well-adjusted children'.
Available information would have confirmed Mick Philpott as 'manipulative and controlling' but there was little known at the time about violence in the household, and no grounds for statutory intervention, it found.
Records reviewed included several references to the adult relationships, the report said, 'but none indicate any concerns'.
Information pointing to tension between Philpott and his two lovers only emerged after the deaths of the children, the report said.
Glenys Johnston OBE, the independent overview report author said: "The review has been comprehensive with full co-operation from all agencies involved.
"Despite the horrific deaths of these children there are few areas for learning for professionals.
"The sad truth is that no one could have predicted or prevented the events that took place on 11 May 2012."
Mick Philpott was handed a life sentence with a minimum term of 15 years after being branded a ''disturbingly dangerous' man.
His wife Mairead, who is likely to be released after serving half of her 17-year term, also took part in a plan to set fire to the couple's home in Victory Road on May 11 2012.
Their friend Paul Mosley was also jailed for 17 years after taking part in the plot.