The family of Henry Vincent laid flowers near to the home of Richard Osborn-Brooks, 78, who was cleared over the career criminal’s killing.
A fence outside the pensioner’s property in Hither Green, southeast London, has become a flashpoint for tensions, with flowers and cards at the memorial being destroyed by locals and then replaced by Vincent’s loved ones.
The shrine, which included handwritten cards from the 37-year-old’s children, was put in place on Monday night only to be pulled down afterwards.
Vicent’s family returned to reattach the tributes on Tuesday only for them to be vandalised again within minutes.
Iain Gordon, who said he was part of the Fair Society group, tore down flowers at 12.30pm on Wednesday as the stand-off rumbled into its third day.
Mr Gordon, from Lewisham, said: “These people are scumbags, scumbags, scumbags.
“If you don’t know why I pulled the flowers down then you aren’t a human being.
“Would you go around allowing someone to stab your parents?
“Would you allow someone to come round with a screwdriver?
“And then be considered human beings?”
Mr Gordon’s act is reported to be the fourth of its kind since the memorial was erected.
One card at the scene, apparently written by one of Vincent’s children, read: “To my daddy, no words can describe the pain and heartache we are going through.
“These people won’t put us down. We love you dad. We miss you so much.”
Vincent died in the early hours of Wednesday 4 April, after a break-in at Mr Osborn-Brook’s home in South Park Crescent.
Police said two men entered the pensioner’s home, with one of them forcing his away into the kitchen while the other man went upstairs.
Vincent, armed with a screwdriver, is said to have been stabbed in the stomach during a struggle with Mr Osborn-Brooks.
Police have not said what object was used to inflict the fatal blow.
Both intruders are said to have fled after the altercation, with Vincent collapsing on nearby Further Green Road.
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He was taken by ambulance to a central London hospital where he later died.
Police are still hunting a suspect named Billy Jeeves in relation to the break-in.