The bodies of Noel Brown, 69, and Marie Brown, 41, were found at Noel Brown's flat in Deptford in the early hours of Monday 4 December.
A father found strangled in his flat alongside his daughter was a convicted sex offender.
"At this early stage we are keeping an open mind regarding the motive", he added.
Ms Brown was last seen at midday on Saturday after going to check on her father, whom had not been seen in nearly two days.
The bodies were found after Ms Brown's family reported her missing when she failed to come home after going to check on her father.
Officers say there were no signs of forced entry to the flat in Deptford and, despite "speculation" Mr Brown's murder was connected to a large gambling win, police keep an open mind.
Police are trying to establish why they were killed but Detective Superintendent Paul Monk said Mr Brown's conviction in 1999 for a sex offence, for which he served four years in prison, was not "screaming out" as a motive.
"I don't know whether he was dismembered at that point or whether he was dismembered after Marie was killed", he added.
The father and daughter found murdered in Deptford were strangled to death and attempts made by the killer to dismember and hide the man's body, detectives disclosed today. If that was you, or you know who it was, please get in contact with us.
"One of the key strands of our investigation is understanding all we can about Noel's life".
Detectives are now appealing for any information about two men who were seen visiting Mr Brown's flat in the days before the murders. He was well known and liked locally.
Mr Monk said Mr Brown, a regular gambler who placed "very small bets" every day at the Paddy Power shop in Deptford High Street, did not visit the bookmakers on Friday and it is possible he was killed before his daughter arrived.
Monk said: "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".
Det Supt Paul Monk said: "This is a deeply distressing time for Noel and Marie's family as they come to terms with their loss". Post-mortem examinations disclosed both were strangled and that attempts were made to dismember and hide the man's body; no attempt was made to dismember his daughter's body.