Tests are being carried out on the body of a 47-year-old man who died along with his 10-year-old daughter in a fire at a terraced house in Hull.
Crews battled to rescue the pair from the building in Wensley Avenue, Cottingham, on Saturday morning.
A post-mortem examination is taking place to establish the cause of his death, tests on his daughter’s body will take place in the coming days.
The cause of the blaze is under investigation, Humberside Police said.
The man was pronounced dead at the scene, the girl died in hospital a short time later.
The father and daughter were the only people in the property at the time, the fire service said.
Neighbour Carl Goodfellow said he saw smoke coming from the building and tried to rescue those inside.
“I was banging on the window to try and get some attention, but there was nothing.
“We did try to alert him, but there was no response.”
Ch Supt Darren Downs said: “We are continuing to support the families of those involved at this very difficult time and our thoughts are with them.
“Investigations into this kind of incident are very complex and take time to complete.
“In the meantime I would ask that people avoid speculating about the circumstances and if you have any information you believe would assist our investigation, please get in touch.”
Mr Downs said there was support available from local agencies and charities for anyone who has been affected by the incident and wanted someone to talk to.