Detectives are searching for a man after a 45-year-old man was found dead in his home in Hounslow.
David Ackerley was found dead on October 8, eight days after police believe he was attacked in the street outside his flat.
Police on Wednesday released an image of a man named Jack Hill, who they want to speak to in relation to Mr Ackerley's death, which is being treated as murder.
Mr Hill is believed to be around 22 years old, and is sometimes known as 'Jimmy' or 'Jimmy Brazil'.
Scotland Yard said he was about 6ft2, of athletic build and has hazel eyes. He has dark blonde or light brown curtain style hair and a surgical scar on his right wrist.
Detectives urged anyone who knows where Mr Hill is to get in touch, adding Mr Ackerley's grieving relatives have "many questions about what happened to him".
Mr Ackerley was reported missing around 9.30am on Sunday, October 8.
Police found him dead a short while later, after visiting his home in Cedar Court, Boston Manor Road.
A post-mortem later determined brain swelling and a bleed on the brain as the primary cause of his death.
Officers believe Mr Ackerley was assaulted outside his home eight days before his body was discovered - between 6.15pm and 6.30pm on Saturday, September 30.
He is understood to have sustained an injury to his face in the assault, which required hospital treatment.
The incident was reportedly being investigated by police prior to the discovery of Mr Ackerley's body.
The Met Police previously described Mr Ackerley as someone who "had his vulnerabilities", and who "many people" in the local area were likely to know.
Detective Chief Inspector Geoff Grogan said on Wednesday: "David's grieving family have many questions about what happened to him, and we are now trying to provide them with answers.
"A man has lost his life and it's important that we uncover what happened to get justice for David and his family.
"This is why it's really important that anyone who knows the whereabouts of Jack Hill, or has any information that might help us with our investigations, should get in touch.
“Please look at these images carefully. Do you recognise this man? Do you have any information about his whereabouts?
"If so, please get in touch with us. You can do some by calling 101 or post @MetCC reference 0524683/23 or to remain 100% anonymous contact the independent charity Crimestoppers on 0800 555 111."
