A mother who knew one of the children found dead along with three others at a home in Norfolk has described her as a "lovely, lovely girl".
Officers discovered the bodies of 45-year-old Bartlomiej Kuczynski and two girls - thought to be his two young daughters - after forcing their way into the property in Allan Bedford Crescent, Costessey, near Norwich, on Friday morning.
Alongside them, the body of a 36-year-old woman, said to be part of the same family, was also discovered.
Norfolk Police said all four had injuries. A post-mortem is set to take place to investigate the cause of their deaths.
Meanwhile, the force has also referred itself to the police watchdog after revealing an emergency 999 call was earlier made by a man from the address, but police failed to respond.
Nina Crisan, whose son knew one of the girls, named Jasmine, described her as a "very, very sweet girl".
"She had very calm and cool energy, as my son would say," she told Sky News. "She was just a lovely, lovely, lovely kid."
She said the incident had come as an "absolute shock" to those who lived in the area.
"[It's just] absolute shock, absolute shock and devastation.
"This is a really close community. And we all, even if we don't know each other directly, sort of know each other through, the children, or through dog walking."
'She never held a grudge'
A boy who knew Jasmine, speaking anonymously to Sky News, said: "We grew up together. She never held a grudge, she was always kind and caring to everyone."
He added: "I never really thought what my last words to her would be."
Another said: "She used to play with my little sister in the park, she used to look out for her. It is really sad for the whole community."
An emergency 999 call was made from the address at around 6am, by a man, but police failed to respond.
Officers later forced their way into the property after being alerted by a member of the public, who was concerned for the welfare of the people inside, shortly before 7am.
The Norfolk force has referred itself to the Independent Office of Police Conduct (IOPC) watchdog in relation to the 6am call, "to which police resources were not deployed".
Police had already contacted the IOPC over the incident because officers attended the property on 14 December last year in relation to a missing person inquiry.
Police 'not looking for anyone else'
Detectives have been carrying out house-to-house inquiries, speaking with witnesses and examining CCTV footage.
Detective Chief Inspector Chris Burgess, who is leading the investigation, said on Friday: "We've spoken to witnesses and neighbours, carried out house-to-house inquiries, examined local CCTV and completed initial scene investigations.
"As a result of this, we're not looking for anyone else in connection with the incident.
"This is a tragic incident, distressing for all involved and it is clear from the reaction it's caused a lot of shock and upset in the local community."