Detectives have launched a murder investigation after John Murphy, aged 50, was found fatally injured in a flat in Baylis Road, Waterloo.
Police and the ambulance service were called at about 9.30am on Friday to reports of a assault at a flat in Baylis Road.
John Murphy, aged 50, was taken to St Thomas' Hospital where he died on Saturday evening.
A post mortem gave cause of death as a head injury.
Four people have been arrested in connection with this investigation.
A woman and a man have since been released.
Two men remain in custody at separate police stations in central and south London.
Officers from the Homicide and Serious Crime Command based at Sutton are investigating.
Anyone with information is asked to contact the incident room on 020 8721 4205 or, call Crimestoppers anonymously on 0800 555 111.