A seven-year-old girl died days after being rescued from a house fire after the arrest of a teenager, suspected of arson.
The fire of the terraced house in Darlington was reported around 13:50 Saturday.
The emergency services fought to save the girl from the house and she was rushed to the hospital.
But she sadly passed away on Wednesday, Durham police said.
A 16-year-old boy was arrested on suspicion of arson, but has since been released under investigation, said a police spokesman.
Detective Inspector Traci McNally of Durham Police said: "A police investigation is under way.
"Our thoughts are with the girl's family and friends as a result of this tragic incident."