A woman has been arrested on suspicion of murder after five children died in a house fire.
A sixth child has been taken to hospital for specialist treatment following the blaze in a semi-detached house in Allenton in Derby.
Derbyshire's Assistant Chief Constable Steve Cotterill revealed news of the arrest at a press conference but he stressed that detectives were keeping an "open mind" about the cause of the fire.
The woman arrested is in her 20s.
The children's parents. neighbours and firefighters fought to rescue them from the first floor of the council house.
Mr Cotterill said the father had made a "valiant attempt" to save the youngsters, who were aged between five and ten.
All five children went to St George's Catholic Primary School in Littleover, Derby, a school spokeswoman said.
A statement from the school said: "We extend our deepest sympathies to the family and community at this sad time.
"Whilst this is under police investigation, we are unable to make further comment."