A five-year-old boy has been critically injured in a house fire which also hurt a woman and two other children.
The woman, 28, is believed to be the children's mother, and her injuries following the blaze on Wentworth Road, Rugby, are described as serious.
The condition of the other children, a boy aged 10 and girl aged eight, was said by the ambulance service to be less grave than the younger boy.
All four are being treated in hospital for burns.
Warwickshire Police says the fire, which broke out about 03:00 GMT, is being treated as suspicious.
The semi-detached home suffered "significant fire damage", according to the ambulance service.
Neighbours reported hearing a woman frantically calling for help.
Gary Osborne said: "There was a small amount of smoke, not a lot, a bit like a foggy mist, and then all of a sudden there were just flames.... up the side of the house."
Gemma Osborne said "the mother was shouting to say to help her" and "to get the rest of the stuff out the house".
The children are being treated at Birmingham Children's Hospital, while the woman is being cared for at another hospital in the city.
Det Insp Paul Thompson said it was "an extremely serious incident".