The house fire that left two women and three children dead was "severe", a spokesman for South Yorkshire Fire and Rescue said.
He said: "Our investigators are arriving here at 9am, so we we will know more later on this morning."
More top news
Noela Rukundo was snatched off the street after her husband paid hitmen to murder her – but lived to tell the tale.
An 11-year-old girl has told police of her terror when she had to fight off a man who she claims tried to get her into his van.
Roger the kangaroo has picked up thousands of online fans after his owner posted a picture of him flexing his impressive muscles.