A man in his 20s lost his hand in an explosion at a house in Liverpool.
A woman and a boy were also treated for smoke inhalation after the house fire, where the roof collapsed, near Liverpool FC's stadium on Anfield Road.
Neighbours reported hearing three loud bangs and said they saw flames coming out of the roof at about 17:30 BST on Tuesday.
The man who lost his hand is being treated in the major trauma unit at Aintree University Hospital.
One neighbour said: "One of the people had his hand blown off and two others were just covered in black."
She added: "There were fireworks coming out of the roof, it was just mayhem."
Another neighbour said: "There was just three loud explosions and then the flames coming through the roof."
Three fire engines were sent to the scene, Merseyside Fire and Rescue Service said.
A joint police and fire service investigation is taking place.