Two girls, aged three and one, died in hospital after the blaze early on Sunday morning.
A mother remains in a critical condition after a flat fire which killed her two children in Nottingham.
The girls, aged three and one, died in hospital after the blaze in Fairlisle Close, Clifton, on Sunday morning.
A 31-year-old man from Clifton has been arrested on suspicion of murder. He is also being questioned on suspicion of attempted murder.
The girls’ mother, a 28-year-old woman, remains critically ill in hospital, police confirmed.
Insp Karl Thomas, from Nottinghamshire Police, said: “We will turn every single stone to make sure the family will get justice.”
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