A teenage boy has died and five members of a family are in hospital after a suspected arson attack at a house in Barnsley.
Neighbours said a woman escaped the fire by jumping from a window
The teenager is believed to be 15 but a formal identification has yet to be carried out.
The five family members were rescued from the house in Kitchen Road, Wombwell, on Friday morning and taken to Barnsley District General Hospital.
A boy of 14 has been arrested in connection with the incident.
A neighbour described being woken by "screaming, shouting and banging" coming from the burning house.
"I ran downstairs in my nightie and looked down the street," the woman told BBC Radio Sheffield.
"By the time I got down everything was ablaze. I feel absolutely sick, it is just a total shock waking up to see all this happening. It's horrible."
A South Yorkshire Police spokesman said a 44-year-old woman was being treated in hospital for serious burns.
The other injured family members, a girl of 12, and two men aged 20 and 23, needed hospital treatment for burns and the effects of breathing in smoke.
A woman of 18 was released from hospital after treatment.