Police did not respond to a 999 call made by a man from a home an hour before he, his two daughters and a woman were found dead there, it has emerged.
The bodies of structural engineer Bartlomiaj Kuczynski, Jasmin Kuczynska, 12, and her seven-year-old sister, and a 36-year-old woman, were discovered at the property in Allan Bedford Crescent at the Queen's Hill estate in Costessey, near Norwich, at around 7.15am on Friday.
Norfolk Police has revealed that a 999 call was made by a man from the house at 6am but they did not deploy resources to the address.
This newspaper understands that it was made by Mr Kuczynski.
No more is known at this stage about the nature of the call.
Police were then called again at just before 7am, after a member of the public raised concerns for the welfare of people inside.
After this call, officers were sent to the house at around 7.15am and they forced entry and found the bodies.
Police said the 36-year-old woman found dead “was visiting and didn’t live at the property”.
The force has referred itself to the Independent Office of Police Conduct (IOPC) regarding the 6am call.
READ MORE: Norwich father found dead with daughters had 'gone missing'
It is the second referral to the IOPC and the first one relates to police contact at the address on December 14, which related to a missing person enquiry.
Police officers have been carrying out additional patrols in Costessey today as detectives continue to investigate the circumstances of the tragedy.
A police cordon remains in place and forensic investigations are continuing inside the property.
Detectives have been carrying out house-to-house enquiries, speaking with witnesses and they are examining local CCTV footage.
READ MORE: Man named after four family members found dead in Norwich
Detective Chief Inspector Chris Burgess, from the Norfolk and Suffolk Major Investigation Team, said: "We have had a heavy police presence in the area since yesterday morning and there is understandably concern in the local community.
"However, their help and support in the investigation has been unwavering and on behalf of everyone involved in this devastating incident, we are extremely grateful for that.
“Today, the focus of our enquiries remains at the address and we’re examining local CCTV.
“While we are still piecing together what’s happened, at this stage we remain satisfied that this is an isolated incident.”
All four people were found with injuries and post-mortem examinations will be held in due course to establish the cause of death.
Jasmin attended Taverham High School while her sister was a pupil at Queen's Hill Primary School.
Flowers have been left close to the scene and the children have been described by neighbours as "beautiful girls."
Mother-of-two Jocelyn Atienza, 50, who lives nearby, said: "It is just awful. The two girls were lovely sisters and beautiful girls.
"They were nice girls who were a little shy. We used to see them walking around together. They would look really happy when they were out with friends."
Nina Crisan, whose son knew one of the girls who lived at the house, 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."
Ms Crisan also described the family as "very friendly" and said the incident had come as an "absolute shock" to local residents.
DCI Burgess added: “We are aware of commentary on social media and in news media, however, I would emphasise that formal identification is yet to take place.
"As I said yesterday, we believe the man and two children lived at the address, and while the woman was staying there, she wasn’t a permanent resident.”
Anyone with any information is asked to get in touch, quoting crime reference NC-19012024-39, via norfolk.police.uk/tell-us or phone 101.
Officers want to hear from anyone who may have been in the Allan Bedford Crescent area earlier in the morning and who may have seen or heard anything that could assist enquiries.
People can also contact the independent charity Crimestoppers anonymously on 0800 555 111, or via their online form at crimestoppers-uk.org.
Churches opened today so people could pay tribute to the victims.
Bishop of Norwich the Rt Rev Graham Usher tweeted: "Prayers for all impacted by this tragic news, especially the wider family and people from Costessey. I’ve spoken to our local clergy who are offering support in the communities they serve and will be opening churches for those who want to come and pray/talk."
The Rev Laura Montgomery, rector of the Easton Benefice and the vicar of Queen's Hills, lives and ministers on the estate.
She said: "I live here on the Queen's Hills estate and we are all shocked by this terrible tragedy. My prayers are with all impacted by these events. We are a close knit community and the grief and shock will be with us all for a long time. As the local vicar I am here to support the local community. I will be out and about on the estate in the coming days if anyone needs to talk. The parish church in Easton remains open with a space for anyone who wishes to light a candle, reflect and pray."
The Diocese of Norwich Facebook account wrote: “Our thoughts and prayers are with all those impacted by the tragic news in Costessey.”
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