Three children and one adult were taken to hospital with smoke inhalation after a fire gutted a house in Conwy county.
North Wales Fire and Rescue Service said four people were taken to hospital after a blaze caused "100% damage" to a house in Beechmere Rise, Mochdre, just after 07:30 BST.
It is understood the children have since been released but the adult's injuries are not known.
Two neighbouring homes were damaged when smoke got into the roof spaces.
An investigation into the cause of the blaze is under way.