A man is being quizzed on suspicion of murdering Fatoumatta Hydara and her young children.
A husband has paid tribute to his wife and two young daughters who died after a flat fire.
One-year-old Naeemah Drammeh and Fatimah Drammeh, aged three, were taken to hospital but later died after the fire in Fairisle Close, Clifton, Nottingham, on Sunday morning.
Their mother, 28-year-old Fatoumatta Hydara, was put on a life-support machine but died on Tuesday.
Aboubacarr Drammeh, 40, said he would “deeply miss” his family.
An investigation found the fire, which was in a first floor flat of a two-storey property, was started deliberately.
A 31-year-old man, from Clifton, has been arrested on suspicion of murder and remains in custody.
Mr Drammeh – who flew back from the US after the fire – said his wife, a former voluntary worker, had lived “a short but a very beautiful and fulfilling life”.
“Fatoumatta was a very happy, bubbly woman who wouldn’t have the heart to hurt a fly,” he said.
“It is therefore inconceivable to think who might have committed this cruel crime against my family.”
Mr Drammeh also thanked the Ahmadi Muslim community in Nottinghamshire, the Gambian community, neighbours and well-wishers for their support.
Nottinghamshire Police were granted an additional 36 hours to question the arrested man on Tuesday.
The force has urged anyone who was in and around Fairisle Close between 00:00 and 04:30 GMT on Sunday to speak to officers.
Det Ch Insp Mark Sinski said: “This is very much an active investigation, so I’d ask anyone who has any footage from the surrounding area they haven’t sent to us yet or has any information that could assist our inquiries, to please get in touch.
“No words can describe the pain the family of the victims are all feeling right now and we are doing everything possible to get them the justice they deserve.
“Every piece of evidence we can gather will get us closer to achieving that goal.”
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