Investigators have narrowed down the location of faulty electrics which sparked a fatal house fire in Derbyshire last week.
Experts say the wiring which caused the blaze was situated between the ground and first floor of the house in North Wingfield.
Two young boys, their mother and a family friend were all killed in the fire, which happened on November 20.
A spokesman for Derbyshire Fire & Rescue Service said:
We would once again like to convey our thoughts and sympathy to the families of the deceased at this very distressing time.