69 year old, Noel Brown, was jailed for 9 years after abusing 2 girls.
He was released in 2004.
He was found dead next to his daughter Marie, 41, on Monday.
Marie had not heard from her Dad for 2 days and went round to check on him.
It is believed she was strangled to death after walking in on vigilantes chopping up Noel’s body.
Superintendent Paul Monk said, “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.
He went on to say, “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.
“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, knew his lifestyle and knew people he may associate with.
There were no signs of a disturbance so I don’t think it’s a burglary or robbery or anything of that nature.
Noel Brown was allegedly targeted by anti-paedophile gangs online.