Detectives investigating the double murder of a sex offender and his daughter are looking into whether they were killed by a vigilante.
Noel Brown, 69, was found dismembered at his flat in Deptford, southeast London on Monday (4 December) after being strangled to death.
His daughter, Marie Brown, 41, was found dead beside her father, also strangled.
Police are probing whether the nursery worker may have been murdered after disturbing her father's killer(s) as they cut up his body in his flat.
Detectives are also looking into the possibility the killings were the work of a vigilante, or vigilantes, in retaliation over Noel Brown's previous conviction for child sex crimes.
He was jailed in 1999 and served four years of a six-year sentence for offences involving the daughters of a family friend, The Times reported. The two girls are thought to have been under the age of 10.
Detective Superintendent Paul Monk said that while his criminal past was not "screaming out" as a motive, it was one line of inquiry.
"One of the possibilities I'm investigating is that these people were known to Noel so I'm particularly keen to hear from anybody that knew Noel," Det Supt Monk said.
He said officers do not believe the motive was burglary or robbery, and that nothing had happened in Brown's life since his release from prison that would suggest someone wanted him dead.
Det Supt Monk added: "There were no signs of forced entry and I think Marie probably went to the address on the Saturday and may have disturbed the attacker or attackers ... while her father's body was being dismembered."
He said he was aware of speculation that Brown, a regular visitor of his local betting shop, may have been killed over a large gambling win, but that "at this time there is no evidence to suggest this was the case".
So far, no arrests have been made.
Police say Brown was last seen alive and well at his flat by a neighbour at 8pm last Thursday (30 November).
At around midday on Saturday, his daughter Marie went to the property in New Butt Lane to check on her father after becoming concerned for his welfare.
Police were contacted by a member of Marie's family at 0.30am the following Monday after she had failed to return to her home in Southwark.
Officers went to Brown's flat in New Butt Lane around two hours later and forced entry to the property. Their bodies were then found inside.
Det Supt Monk said:"Our investigation is fast moving and making progress every day. I want to reassure people that we are doing all we can to find those responsible for the murders of Noel and Marie.
"I am asking the public to help us with any information they may have that could assist our investigation – specifically about two men who visited Noel's flat in the days prior to his death. If that was you, or you know who it was, please get in contact with us.
"At this early stage we are keeping an open mind regarding the motive, however it was clear to the responding officers that there were no signs of forced entry to the property. One of our key lines of enquiry is to establish if the suspects or suspects were known to Noel and if Marie disturbed them."
He continued: "One of the key strands of our investigation is understanding all we can about Noel's life. He was well known and liked locally.
"We know that Noel used to go to his local betting shop, Paddy Power, in Deptford High Street and had in fact been there during the day he was last seen alive on 30 November. There has been speculation that his murder was as a result of a large gambling win, however at this time there is no evidence to suggest this was the case.
"I am keen to hear from anyone who saw Noel in the days leading up to his death or saw anyone or anything unusual in or around New Butt Lane, SE8 during that time.
"This is a deeply distressing time for Noel and Marie's family as they come to terms with their loss."
Post-mortem examinations at Greenwich Mortuary held on Tuesday and Wednesday confirmed that both Noel and Marie died as a result of strangulation.
Anyone with any information, no matter how small, is asked to contact the investigation team on 020 8721 4205, or 101. You can also tweet police @MetCC. To remain anonymous please call Crimestoppers on 0800 555 111.