Murder squad detectives have named a man who was found dead at a flat in North Yorkshire as Richard Ian Walker.
Mr Walker, 50, was discovered at the property on Princess Street in his home town of Scarborough on Thursday afternoon.
Police today revealed he had suffered injuries consistent with a “violent and sustained assault”.
Two men, aged 42 and 39, have been arrested on suspicion of murder and today remained in custody.
A third man, aged 54, has been released on bail after being arrested on suspicion of murder overnight on Friday into Saturday.
Another man, also aged 54, has been released with no further action after being arrested on Thursday.
Police are appealing for witnesses to come forward to help their efforts to establish a detailed sequence of events leading up to the discovery of Mr Walker’s body.
Det Supt Dai Malyn, head of North Yorkshire Police’s major crime unit said: “Ricky Walker’s injuries were the result of a violent and sustained assault.
“Detectives are carrying out a detailed investigation to establish the events leading up to his death at the flat on Princess Street at around 4.30pm last Thursday.
“To help our enquiries, we are keen to trace Ricky’s movements since the morning of Tuesday 18 October 2016 to the time of his death on Thursday.
“We believe Ricky was wearing a grey cap, dark jacket and was often seen to be carrying a satchel-type bag.”
Det Supt Malyn added: “The last known sighting of Ricky alive was on Wednesday 19 October 2016 at 3.15pm on St Helens Square, Scarborough.
“There was an altercation between an elderly couple driving a dark-coloured Vauxhall estate car.
“We know Ricky wasn’t involved in this altercation, but that he was a nearby witness to it.
“I am appealing for the couple from the car to come forward as soon as possible as we believe they may have important information that could assist the investigation.”
Anyone who can help is asked to ring the incident room on 01609 643252 or Crimestoppers anonymously on 0800 555111.